diff --git a/backend/internal/service/openai_oauth_service.go b/backend/internal/service/openai_oauth_service.go
index 0a1266d9..0f004b01 100644
--- a/backend/internal/service/openai_oauth_service.go
+++ b/backend/internal/service/openai_oauth_service.go
@@ -502,6 +502,25 @@ func (s *OpenAIOAuthService) RefreshAccountToken(ctx context.Context, account *A
 
 	refreshToken := account.GetCredential("refresh_token")
 	if refreshToken == "" {
+		accessToken := account.GetCredential("access_token")
+		if accessToken != "" {
+			tokenInfo := &OpenAITokenInfo{
+				AccessToken:      accessToken,
+				RefreshToken:     "",
+				IDToken:          account.GetCredential("id_token"),
+				ClientID:         account.GetCredential("client_id"),
+				Email:            account.GetCredential("email"),
+				ChatGPTAccountID: account.GetCredential("chatgpt_account_id"),
+				ChatGPTUserID:    account.GetCredential("chatgpt_user_id"),
+				OrganizationID:   account.GetCredential("organization_id"),
+				PlanType:         account.GetCredential("plan_type"),
+			}
+			if expiresAt := account.GetCredentialAsTime("expires_at"); expiresAt != nil {
+				tokenInfo.ExpiresAt = expiresAt.Unix()
+				tokenInfo.ExpiresIn = int64(time.Until(*expiresAt).Seconds())
+			}
+			return tokenInfo, nil
+		}
 		return nil, infraerrors.New(http.StatusBadRequest, "OPENAI_OAUTH_NO_REFRESH_TOKEN", "no refresh token available")
 	}
 
diff --git a/backend/internal/service/openai_oauth_service_refresh_test.go b/backend/internal/service/openai_oauth_service_refresh_test.go
new file mode 100644
index 00000000..a31eb8cb
--- /dev/null
+++ b/backend/internal/service/openai_oauth_service_refresh_test.go
@@ -0,0 +1,54 @@
+package service
+
+import (
+	"context"
+	"errors"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/pkg/openai"
+	"github.com/stretchr/testify/require"
+)
+
+type openaiOAuthClientRefreshStub struct {
+	refreshCalls int32
+}
+
+func (s *openaiOAuthClientRefreshStub) ExchangeCode(ctx context.Context, code, codeVerifier, redirectURI, proxyURL, clientID string) (*openai.TokenResponse, error) {
+	return nil, errors.New("not implemented")
+}
+
+func (s *openaiOAuthClientRefreshStub) RefreshToken(ctx context.Context, refreshToken, proxyURL string) (*openai.TokenResponse, error) {
+	atomic.AddInt32(&s.refreshCalls, 1)
+	return nil, errors.New("not implemented")
+}
+
+func (s *openaiOAuthClientRefreshStub) RefreshTokenWithClientID(ctx context.Context, refreshToken, proxyURL string, clientID string) (*openai.TokenResponse, error) {
+	atomic.AddInt32(&s.refreshCalls, 1)
+	return nil, errors.New("not implemented")
+}
+
+func TestOpenAIOAuthService_RefreshAccountToken_NoRefreshTokenUsesExistingAccessToken(t *testing.T) {
+	client := &openaiOAuthClientRefreshStub{}
+	svc := NewOpenAIOAuthService(nil, client)
+
+	expiresAt := time.Now().Add(30 * time.Minute).UTC().Format(time.RFC3339)
+	account := &Account{
+		ID:       77,
+		Platform: PlatformOpenAI,
+		Type:     AccountTypeOAuth,
+		Credentials: map[string]any{
+			"access_token": "existing-access-token",
+			"expires_at":   expiresAt,
+			"client_id":    "client-id-1",
+		},
+	}
+
+	info, err := svc.RefreshAccountToken(context.Background(), account)
+	require.NoError(t, err)
+	require.NotNil(t, info)
+	require.Equal(t, "existing-access-token", info.AccessToken)
+	require.Equal(t, "client-id-1", info.ClientID)
+	require.Zero(t, atomic.LoadInt32(&client.refreshCalls), "existing access token should be reused without calling refresh")
+}
diff --git a/backend/internal/service/token_refresh_service.go b/backend/internal/service/token_refresh_service.go
index eb3e5592..f521c972 100644
--- a/backend/internal/service/token_refresh_service.go
+++ b/backend/internal/service/token_refresh_service.go
@@ -430,6 +430,7 @@ func isNonRetryableRefreshError(err error) bool {
 		"unauthorized_client", // 客户端未授权
 		"access_denied",       // 访问被拒绝
 		"missing_project_id",  // 缺少 project_id
+		"no refresh token available",
 	}
 	for _, needle := range nonRetryable {
 		if strings.Contains(msg, needle) {
diff --git a/backend/internal/service/token_refresh_service_test.go b/backend/internal/service/token_refresh_service_test.go
index 60ba4a96..2179a85e 100644
--- a/backend/internal/service/token_refresh_service_test.go
+++ b/backend/internal/service/token_refresh_service_test.go
@@ -19,6 +19,7 @@ type tokenRefreshAccountRepo struct {
 	updateCredentialsCalls int
 	setErrorCalls          int
 	clearTempCalls         int
+	setTempUnschedCalls    int
 	lastAccount            *Account
 	updateErr              error
 }
@@ -58,6 +59,11 @@ func (r *tokenRefreshAccountRepo) ClearTempUnschedulable(ctx context.Context, id
 	return nil
 }
 
+func (r *tokenRefreshAccountRepo) SetTempUnschedulable(ctx context.Context, id int64, until time.Time, reason string) error {
+	r.setTempUnschedCalls++
+	return nil
+}
+
 type tokenCacheInvalidatorStub struct {
 	calls int
 	err   error
@@ -490,6 +496,31 @@ func TestTokenRefreshService_RefreshWithRetry_NonRetryableErrorAllPlatforms(t *t
 	}
 }
 
+func TestTokenRefreshService_RefreshWithRetry_NoRefreshTokenDoesNotTempUnschedule(t *testing.T) {
+	repo := &tokenRefreshAccountRepo{}
+	cfg := &config.Config{
+		TokenRefresh: config.TokenRefreshConfig{
+			MaxRetries:          2,
+			RetryBackoffSeconds: 0,
+		},
+	}
+	service := NewTokenRefreshService(repo, nil, nil, nil, nil, nil, nil, cfg, nil)
+	account := &Account{
+		ID:       18,
+		Platform: PlatformOpenAI,
+		Type:     AccountTypeOAuth,
+	}
+	refresher := &tokenRefresherStub{
+		err: errors.New("no refresh token available"),
+	}
+
+	err := service.refreshWithRetry(context.Background(), account, refresher, refresher, time.Hour)
+	require.Error(t, err)
+	require.Equal(t, 0, repo.updateCalls)
+	require.Equal(t, 0, repo.setTempUnschedCalls, "missing refresh token should not mark the account temp unschedulable")
+	require.Equal(t, 1, repo.setErrorCalls, "missing refresh token should be treated as a non-retryable credential state")
+}
+
 // TestIsNonRetryableRefreshError 测试不可重试错误判断
 func TestIsNonRetryableRefreshError(t *testing.T) {
 	tests := []struct {
@@ -503,6 +534,7 @@ func TestIsNonRetryableRefreshError(t *testing.T) {
 		{name: "invalid_client", err: errors.New("invalid_client"), expected: true},
 		{name: "unauthorized_client", err: errors.New("unauthorized_client"), expected: true},
 		{name: "access_denied", err: errors.New("access_denied"), expected: true},
+		{name: "no_refresh_token", err: errors.New("no refresh token available"), expected: true},
 		{name: "invalid_grant_with_desc", err: errors.New("Error: invalid_grant - token revoked"), expected: true},
 		{name: "case_insensitive", err: errors.New("INVALID_GRANT"), expected: true},
 	}