diff --git a/CHANGELOG.md b/CHANGELOG.md
index a31289b..c902a25 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## Unreleased
 
 ### Added
+- Auth: add `auth credentials remove` to delete stored OAuth client credentials and associated refresh tokens. (#473) — thanks @yamagucci.
 - Gmail: add `gmail autoreply` to reply once to matching messages, label the thread for dedupe, and optionally archive/mark read. Includes docs and regression coverage for skip/reply flows.
 - Gmail: add `gmail messages search --full` to print complete message bodies instead of truncating text output. (#447) — thanks @GodsBoy.
 - Drive: allow `drive share --role commenter` for comment-only sharing. (#443) — thanks @pavelzak.
diff --git a/README.md b/README.md
index a5fc31b..6407400 100644
--- a/README.md
+++ b/README.md
@@ -599,6 +599,8 @@ Flag aliases:
 ```bash
 gog auth credentials <path>           # Store OAuth client credentials
 gog auth credentials list             # List stored OAuth client credentials
+gog auth credentials remove work      # Remove one OAuth client plus its tokens/domain mappings
+gog auth credentials remove all       # Remove all stored OAuth clients plus their tokens/domain mappings
 gog --client work auth credentials <path>  # Store named OAuth client credentials
 gog auth add <email>                  # Authorize and store refresh token
 gog auth add <email> --services gmail --gmail-scope readonly  # Gmail read-only token
diff --git a/docs/spec.md b/docs/spec.md
index a8a06ad..8c4b03d 100644
--- a/docs/spec.md
+++ b/docs/spec.md
@@ -80,6 +80,7 @@ Implementation: `internal/ui/ui.go`.
   - `gog auth credentials <credentials.json>`
   - `gog --client <name> auth credentials <credentials.json>`
   - `gog auth credentials list`
+  - `gog auth credentials remove [<client>|all]`
 - Supports Google’s downloaded JSON format:
   - `installed.client_id/client_secret` or `web.client_id/client_secret`
 
@@ -163,6 +164,7 @@ Flag aliases:
 
 - `gog auth credentials <credentials.json|->`
 - `gog auth credentials list`
+- `gog auth credentials remove [<client>|all]`
 - `gog --client <name> auth credentials <credentials.json|->`
 - `gog auth add <email> [--services user|all|gmail,calendar,chat,classroom,drive,docs,slides,contacts,tasks,sheets,people,forms,appscript,ads,groups,keep,admin] [--readonly] [--drive-scope full|readonly|file] [--gmail-scope full|readonly] [--extra-scopes CSV] [--manual] [--remote] [--step 1|2] [--auth-url URL] [--listen-addr HOST[:PORT]] [--redirect-host HOST] [--timeout DURATION] [--force-consent]`
 - `gog auth services [--markdown]`
diff --git a/internal/cmd/auth_credentials.go b/internal/cmd/auth_credentials.go
index 61d5235..ef29eb6 100644
--- a/internal/cmd/auth_credentials.go
+++ b/internal/cmd/auth_credentials.go
@@ -15,8 +15,9 @@ import (
 )
 
 type AuthCredentialsCmd struct {
-	Set  AuthCredentialsSetCmd  `cmd:"" default:"withargs" help:"Store OAuth client credentials"`
-	List AuthCredentialsListCmd `cmd:"" name:"list" help:"List stored OAuth client credentials"`
+	Set    AuthCredentialsSetCmd    `cmd:"" default:"withargs" help:"Store OAuth client credentials"`
+	List   AuthCredentialsListCmd   `cmd:"" name:"list" help:"List stored OAuth client credentials"`
+	Remove AuthCredentialsRemoveCmd `cmd:"" name:"remove" help:"Remove stored OAuth client credentials"`
 }
 
 type AuthCredentialsSetCmd struct {
@@ -160,3 +161,202 @@ func (c *AuthCredentialsListCmd) Run(ctx context.Context, _ *RootFlags) error {
 	}
 	return nil
 }
+
+type AuthCredentialsRemoveCmd struct {
+	Client string `arg:"" optional:"" name:"client" help:"Client name to remove (omit for default, or 'all' to remove every client)"`
+}
+
+type authCredentialsRemovalResult struct {
+	Client         string   `json:"client"`
+	TokensRemoved  []string `json:"tokens_removed,omitempty"`
+	DomainsRemoved []string `json:"domains_removed,omitempty"`
+}
+
+func (c *AuthCredentialsRemoveCmd) Run(ctx context.Context, flags *RootFlags) error {
+	u := ui.FromContext(ctx)
+
+	// Determine target client(s): explicit arg > --client flag > default.
+	target := strings.TrimSpace(c.Client)
+	if target == "" {
+		t, err := normalizeClientForFlag(authclient.ClientOverrideFromContext(ctx))
+		if err != nil {
+			return err
+		}
+		target = t
+	}
+
+	if strings.EqualFold(target, "all") {
+		return c.removeAll(ctx, flags, u)
+	}
+
+	client, err := config.NormalizeClientNameOrDefault(target)
+	if err != nil {
+		return err
+	}
+
+	if dryRunErr := dryRunExit(ctx, flags, "auth.credentials.remove", map[string]any{
+		"client": client,
+	}); dryRunErr != nil {
+		return dryRunErr
+	}
+
+	accounts, err := accountsForClient(client)
+	if err != nil {
+		return err
+	}
+
+	action := fmt.Sprintf("remove OAuth credentials for client %q", client)
+	if len(accounts) > 0 {
+		action += fmt.Sprintf(" and %d associated token(s) (%s)", len(accounts), strings.Join(accounts, ", "))
+	}
+	if confirmErr := confirmDestructiveChecked(ctx, flagsWithoutDryRun(flags), action); confirmErr != nil {
+		return confirmErr
+	}
+
+	if deleteErr := config.DeleteClientCredentialsFor(client); deleteErr != nil {
+		return deleteErr
+	}
+
+	tokensRemoved, err := removeTokensForClient(client, accounts)
+	if err != nil {
+		return err
+	}
+	domainsRemoved, err := removeDomainMappings(client)
+	if err != nil {
+		return err
+	}
+
+	return writeResult(ctx, u,
+		kv("removed", true),
+		kv("client", client),
+		kv("tokens_removed", tokensRemoved),
+		kv("domains_removed", domainsRemoved),
+	)
+}
+
+func (c *AuthCredentialsRemoveCmd) removeAll(ctx context.Context, flags *RootFlags, u *ui.UI) error {
+	creds, err := config.ListClientCredentials()
+	if err != nil {
+		return err
+	}
+	if len(creds) == 0 {
+		return writeResult(ctx, u, kv("removed", 0))
+	}
+
+	names := make([]string, 0, len(creds))
+	planned := make([]authCredentialsRemovalResult, 0, len(creds))
+	for _, info := range creds {
+		names = append(names, info.Client)
+		accounts, accountsErr := accountsForClient(info.Client)
+		if accountsErr != nil {
+			return accountsErr
+		}
+		planned = append(planned, authCredentialsRemovalResult{
+			Client:        info.Client,
+			TokensRemoved: accounts,
+		})
+	}
+	if dryRunErr := dryRunExit(ctx, flags, "auth.credentials.remove_all", planned); dryRunErr != nil {
+		return dryRunErr
+	}
+	if err := confirmDestructiveChecked(ctx, flagsWithoutDryRun(flags), fmt.Sprintf("remove all OAuth credentials (%s)", strings.Join(names, ", "))); err != nil {
+		return err
+	}
+
+	var allTokens []string
+	var allDomains []string
+	for _, item := range planned {
+		if err := config.DeleteClientCredentialsFor(item.Client); err != nil {
+			return err
+		}
+		tokens, err := removeTokensForClient(item.Client, item.TokensRemoved)
+		if err != nil {
+			return err
+		}
+		allTokens = append(allTokens, tokens...)
+		domains, err := removeDomainMappings(item.Client)
+		if err != nil {
+			return err
+		}
+		allDomains = append(allDomains, domains...)
+	}
+	sort.Strings(allTokens)
+	sort.Strings(allDomains)
+
+	return writeResult(ctx, u,
+		kv("removed", len(creds)),
+		kv("clients", names),
+		kv("tokens_removed", allTokens),
+		kv("domains_removed", allDomains),
+	)
+}
+
+// accountsForClient returns emails that have tokens stored under the given client.
+func accountsForClient(client string) ([]string, error) {
+	store, err := openSecretsStore()
+	if err != nil {
+		return nil, err
+	}
+	tokens, err := store.ListTokens()
+	if err != nil {
+		return nil, err
+	}
+	var emails []string
+	for _, tok := range tokens {
+		tokClient, err := config.NormalizeClientNameOrDefault(tok.Client)
+		if err != nil {
+			continue
+		}
+		if tokClient == client {
+			emails = append(emails, tok.Email)
+		}
+	}
+	sort.Strings(emails)
+	return emails, nil
+}
+
+// removeTokensForClient deletes tokens for the given accounts under the specified client.
+func removeTokensForClient(client string, emails []string) ([]string, error) {
+	if len(emails) == 0 {
+		return nil, nil
+	}
+	store, err := openSecretsStore()
+	if err != nil {
+		return nil, err
+	}
+	var removed []string
+	for _, email := range emails {
+		if err := store.DeleteToken(client, email); err != nil {
+			return removed, fmt.Errorf("delete token for %s: %w", email, err)
+		}
+		removed = append(removed, email)
+	}
+	sort.Strings(removed)
+	return removed, nil
+}
+
+// removeDomainMappings deletes config domain entries that point to the given client.
+func removeDomainMappings(client string) ([]string, error) {
+	cfg, err := config.ReadConfig()
+	if err != nil {
+		return nil, err
+	}
+	var removed []string
+	for domain, mapped := range cfg.ClientDomains {
+		normalized, nerr := config.NormalizeClientNameOrDefault(mapped)
+		if nerr != nil {
+			continue
+		}
+		if normalized == client {
+			removed = append(removed, domain)
+			delete(cfg.ClientDomains, domain)
+		}
+	}
+	if len(removed) > 0 {
+		sort.Strings(removed)
+		if err := config.WriteConfig(cfg); err != nil {
+			return nil, err
+		}
+	}
+	return removed, nil
+}
diff --git a/internal/cmd/execute_auth_credentials_test.go b/internal/cmd/execute_auth_credentials_test.go
index 5e3be5c..1df6592 100644
--- a/internal/cmd/execute_auth_credentials_test.go
+++ b/internal/cmd/execute_auth_credentials_test.go
@@ -2,11 +2,15 @@ package cmd
 
 import (
 	"encoding/json"
+	"errors"
 	"os"
 	"path/filepath"
 	"testing"
 
+	"github.com/99designs/keyring"
+
 	"github.com/steipete/gogcli/internal/config"
+	"github.com/steipete/gogcli/internal/secrets"
 )
 
 func TestExecute_AuthCredentials_JSON(t *testing.T) {
@@ -150,3 +154,148 @@ func TestExecute_AuthCredentialsList_JSON(t *testing.T) {
 		t.Fatalf("missing expected entries: %#v", seen)
 	}
 }
+
+func TestExecute_AuthCredentialsRemove_RemovesCredentialTokenAndDomain(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	t.Setenv("XDG_CONFIG_HOME", filepath.Join(home, "xdg-config"))
+
+	origOpen := openSecretsStore
+	t.Cleanup(func() { openSecretsStore = origOpen })
+
+	store := newMemSecretsStore()
+	openSecretsStore = func() (secrets.Store, error) { return store, nil }
+
+	if err := config.WriteClientCredentialsFor("work", config.ClientCredentials{ClientID: "id", ClientSecret: "sec"}); err != nil {
+		t.Fatalf("WriteClientCredentialsFor: %v", err)
+	}
+	if err := store.SetToken("work", "A@B.COM", secrets.Token{RefreshToken: "rt"}); err != nil {
+		t.Fatalf("SetToken work: %v", err)
+	}
+	if err := store.SetToken(config.DefaultClientName, "default@example.com", secrets.Token{RefreshToken: "rt"}); err != nil {
+		t.Fatalf("SetToken default: %v", err)
+	}
+	if err := config.WriteConfig(config.File{ClientDomains: map[string]string{
+		"example.com": "work",
+		"other.com":   config.DefaultClientName,
+	}}); err != nil {
+		t.Fatalf("WriteConfig: %v", err)
+	}
+
+	out := captureStdout(t, func() {
+		_ = captureStderr(t, func() {
+			if err := Execute([]string{"--json", "--force", "auth", "credentials", "remove", "work"}); err != nil {
+				t.Fatalf("Execute: %v", err)
+			}
+		})
+	})
+
+	var parsed struct {
+		Removed        bool     `json:"removed"`
+		Client         string   `json:"client"`
+		TokensRemoved  []string `json:"tokens_removed"`
+		DomainsRemoved []string `json:"domains_removed"`
+	}
+	if err := json.Unmarshal([]byte(out), &parsed); err != nil {
+		t.Fatalf("json parse: %v\nout=%q", err, out)
+	}
+	if !parsed.Removed || parsed.Client != "work" {
+		t.Fatalf("unexpected remove output: %#v", parsed)
+	}
+	if len(parsed.TokensRemoved) != 1 || parsed.TokensRemoved[0] != "a@b.com" {
+		t.Fatalf("unexpected removed tokens: %#v", parsed.TokensRemoved)
+	}
+	if len(parsed.DomainsRemoved) != 1 || parsed.DomainsRemoved[0] != "example.com" {
+		t.Fatalf("unexpected removed domains: %#v", parsed.DomainsRemoved)
+	}
+	path, err := config.ClientCredentialsPathFor("work")
+	if err != nil {
+		t.Fatalf("ClientCredentialsPathFor: %v", err)
+	}
+	if _, statErr := os.Stat(path); !errors.Is(statErr, os.ErrNotExist) {
+		t.Fatalf("expected work credentials removed, stat err=%v", statErr)
+	}
+	if _, tokenErr := store.GetToken("work", "a@b.com"); !errors.Is(tokenErr, keyring.ErrKeyNotFound) {
+		t.Fatalf("expected work token removed, err=%v", tokenErr)
+	}
+	if _, defaultTokenErr := store.GetToken(config.DefaultClientName, "default@example.com"); defaultTokenErr != nil {
+		t.Fatalf("expected default token retained: %v", defaultTokenErr)
+	}
+	cfg, err := config.ReadConfig()
+	if err != nil {
+		t.Fatalf("ReadConfig: %v", err)
+	}
+	if _, ok := cfg.ClientDomains["example.com"]; ok {
+		t.Fatalf("expected example.com mapping removed: %#v", cfg.ClientDomains)
+	}
+	if cfg.ClientDomains["other.com"] != config.DefaultClientName {
+		t.Fatalf("expected other.com mapping retained: %#v", cfg.ClientDomains)
+	}
+}
+
+func TestExecute_AuthCredentialsRemoveAll(t *testing.T) {
+	home := t.TempDir()
+	t.Setenv("HOME", home)
+	t.Setenv("XDG_CONFIG_HOME", filepath.Join(home, "xdg-config"))
+
+	origOpen := openSecretsStore
+	t.Cleanup(func() { openSecretsStore = origOpen })
+
+	store := newMemSecretsStore()
+	openSecretsStore = func() (secrets.Store, error) { return store, nil }
+
+	for _, client := range []string{config.DefaultClientName, "work"} {
+		if err := config.WriteClientCredentialsFor(client, config.ClientCredentials{ClientID: "id-" + client, ClientSecret: "sec"}); err != nil {
+			t.Fatalf("WriteClientCredentialsFor(%s): %v", client, err)
+		}
+		if err := store.SetToken(client, client+"@example.com", secrets.Token{RefreshToken: "rt"}); err != nil {
+			t.Fatalf("SetToken(%s): %v", client, err)
+		}
+	}
+	if err := config.WriteConfig(config.File{ClientDomains: map[string]string{
+		"default.example": config.DefaultClientName,
+		"work.example":    "work",
+	}}); err != nil {
+		t.Fatalf("WriteConfig: %v", err)
+	}
+
+	out := captureStdout(t, func() {
+		_ = captureStderr(t, func() {
+			if err := Execute([]string{"--json", "--force", "auth", "credentials", "remove", "all"}); err != nil {
+				t.Fatalf("Execute: %v", err)
+			}
+		})
+	})
+
+	var parsed struct {
+		Removed        int      `json:"removed"`
+		Clients        []string `json:"clients"`
+		TokensRemoved  []string `json:"tokens_removed"`
+		DomainsRemoved []string `json:"domains_removed"`
+	}
+	if err := json.Unmarshal([]byte(out), &parsed); err != nil {
+		t.Fatalf("json parse: %v\nout=%q", err, out)
+	}
+	if parsed.Removed != 2 || len(parsed.Clients) != 2 || len(parsed.TokensRemoved) != 2 || len(parsed.DomainsRemoved) != 2 {
+		t.Fatalf("unexpected remove-all output: %#v", parsed)
+	}
+	for _, client := range []string{config.DefaultClientName, "work"} {
+		path, err := config.ClientCredentialsPathFor(client)
+		if err != nil {
+			t.Fatalf("ClientCredentialsPathFor(%s): %v", client, err)
+		}
+		if _, err := os.Stat(path); !errors.Is(err, os.ErrNotExist) {
+			t.Fatalf("expected %s credentials removed, stat err=%v", client, err)
+		}
+		if _, err := store.GetToken(client, client+"@example.com"); !errors.Is(err, keyring.ErrKeyNotFound) {
+			t.Fatalf("expected %s token removed, err=%v", client, err)
+		}
+	}
+	cfg, err := config.ReadConfig()
+	if err != nil {
+		t.Fatalf("ReadConfig: %v", err)
+	}
+	if len(cfg.ClientDomains) != 0 {
+		t.Fatalf("expected all domain mappings removed: %#v", cfg.ClientDomains)
+	}
+}
diff --git a/internal/config/credentials.go b/internal/config/credentials.go
index a82db04..aeae277 100644
--- a/internal/config/credentials.go
+++ b/internal/config/credentials.go
@@ -114,6 +114,23 @@ func ReadClientCredentialsFor(client string) (ClientCredentials, error) {
 	return c, nil
 }
 
+func DeleteClientCredentialsFor(client string) error {
+	path, err := ClientCredentialsPathFor(client)
+	if err != nil {
+		return fmt.Errorf("resolve credentials path: %w", err)
+	}
+
+	if err := os.Remove(path); err != nil {
+		if os.IsNotExist(err) {
+			return &CredentialsMissingError{Path: path, Cause: err}
+		}
+
+		return fmt.Errorf("delete credentials: %w", err)
+	}
+
+	return nil
+}
+
 func ClientCredentialsExists(client string) (bool, error) {
 	path, err := ClientCredentialsPathFor(client)
 	if err != nil {