diff --git a/backend/internal/integration/e2e_gateway_test.go b/backend/internal/integration/e2e_gateway_test.go
index 05cdc85f..ec0b29f7 100644
--- a/backend/internal/integration/e2e_gateway_test.go
+++ b/backend/internal/integration/e2e_gateway_test.go
@@ -57,6 +57,7 @@ var geminiModels = []string{
 	"gemini-2.5-flash-lite",
 	"gemini-3-flash",
 	"gemini-3-pro-low",
+	"gemini-3-pro-high",
 }
 
 func TestMain(m *testing.M) {
@@ -641,6 +642,37 @@ func testClaudeThinkingWithToolHistory(t *testing.T, model string) {
 	t.Logf("✅ thinking 模式工具调用测试通过, id=%v", result["id"])
 }
 
+// TestClaudeMessagesWithGeminiModel 测试在 Claude 端点使用 Gemini 模型
+// 验证：通过 /v1/messages 端点传入 gemini 模型名的场景（含前缀映射）
+// 仅在 Antigravity 模式下运行（ENDPOINT_PREFIX="/antigravity"）
+func TestClaudeMessagesWithGeminiModel(t *testing.T) {
+	if endpointPrefix != "/antigravity" {
+		t.Skip("仅在 Antigravity 模式下运行")
+	}
+
+	// 测试通过 Claude 端点调用 Gemini 模型
+	geminiViaClaude := []string{
+		"gemini-3-flash",       // 直接支持
+		"gemini-3-pro-low",     // 直接支持
+		"gemini-3-pro-high",    // 直接支持
+		"gemini-3-pro",         // 前缀映射 -> gemini-3-pro-high
+		"gemini-3-pro-preview", // 前缀映射 -> gemini-3-pro-high
+	}
+
+	for i, model := range geminiViaClaude {
+		if i > 0 {
+			time.Sleep(testInterval)
+		}
+		t.Run(model+"_通过Claude端点", func(t *testing.T) {
+			testClaudeMessage(t, model, false)
+		})
+		time.Sleep(testInterval)
+		t.Run(model+"_通过Claude端点_流式", func(t *testing.T) {
+			testClaudeMessage(t, model, true)
+		})
+	}
+}
+
 // TestClaudeMessagesWithNoSignature 测试历史 thinking block 不带 signature 的场景
 // 验证：Gemini 模型接受没有 signature 的 thinking block
 func TestClaudeMessagesWithNoSignature(t *testing.T) {
@@ -738,3 +770,30 @@ func testClaudeWithNoSignature(t *testing.T, model string) {
 	}
 	t.Logf("✅ 无 signature thinking 处理测试通过, id=%v", result["id"])
 }
+
+// TestGeminiEndpointWithClaudeModel 测试通过 Gemini 端点调用 Claude 模型
+// 仅在 Antigravity 模式下运行（ENDPOINT_PREFIX="/antigravity"）
+func TestGeminiEndpointWithClaudeModel(t *testing.T) {
+	if endpointPrefix != "/antigravity" {
+		t.Skip("仅在 Antigravity 模式下运行")
+	}
+
+	// 测试通过 Gemini 端点调用 Claude 模型
+	claudeViaGemini := []string{
+		"claude-sonnet-4-5",
+		"claude-opus-4-5-thinking",
+	}
+
+	for i, model := range claudeViaGemini {
+		if i > 0 {
+			time.Sleep(testInterval)
+		}
+		t.Run(model+"_通过Gemini端点", func(t *testing.T) {
+			testGeminiGenerate(t, model, false)
+		})
+		time.Sleep(testInterval)
+		t.Run(model+"_通过Gemini端点_流式", func(t *testing.T) {
+			testGeminiGenerate(t, model, true)
+		})
+	}
+}
diff --git a/backend/internal/service/antigravity_gateway_service.go b/backend/internal/service/antigravity_gateway_service.go
index 5b3bf565..267d7548 100644
--- a/backend/internal/service/antigravity_gateway_service.go
+++ b/backend/internal/service/antigravity_gateway_service.go
@@ -25,7 +25,7 @@ const (
 	antigravityRetryMaxDelay    = 16 * time.Second
 )
 
-// Antigravity 直接支持的模型
+// Antigravity 直接支持的模型（精确匹配透传）
 var antigravitySupportedModels = map[string]bool{
 	"claude-opus-4-5-thinking":   true,
 	"claude-sonnet-4-5":          true,
@@ -36,23 +36,26 @@ var antigravitySupportedModels = map[string]bool{
 	"gemini-3-flash":             true,
 	"gemini-3-pro-low":           true,
 	"gemini-3-pro-high":          true,
-	"gemini-3-pro-preview":       true,
 	"gemini-3-pro-image":         true,
 }
 
-// Antigravity 系统默认模型映射表（不支持 → 支持）
-var antigravityModelMapping = map[string]string{
-	"claude-3-5-sonnet-20241022": "claude-sonnet-4-5",
-	"claude-3-5-sonnet-20240620": "claude-sonnet-4-5",
-	"claude-sonnet-4-5-20250929": "claude-sonnet-4-5-thinking",
-	"claude-opus-4":              "claude-opus-4-5-thinking",
-	"claude-opus-4-5-20251101":   "claude-opus-4-5-thinking",
-	"claude-haiku-4":             "gemini-3-flash",
-	"claude-haiku-4-5":           "gemini-3-flash",
-	"claude-3-haiku-20240307":    "gemini-3-flash",
-	"claude-haiku-4-5-20251001":  "gemini-3-flash",
-	// 生图模型：官方名 → Antigravity 内部名
-	"gemini-3-pro-image-preview": "gemini-3-pro-image",
+// Antigravity 前缀映射表（按前缀长度降序排列，确保最长匹配优先）
+// 用于处理模型版本号变化（如 -20251111, -thinking, -preview 等后缀）
+var antigravityPrefixMapping = []struct {
+	prefix string
+	target string
+}{
+	// 长前缀优先
+	{"gemini-3-pro-image", "gemini-3-pro-image"}, // gemini-3-pro-image-preview 等
+	{"claude-3-5-sonnet", "claude-sonnet-4-5"},   // 旧版 claude-3-5-sonnet-xxx
+	{"claude-sonnet-4-5", "claude-sonnet-4-5"},   // claude-sonnet-4-5-xxx
+	{"claude-haiku-4-5", "gemini-3-flash"},       // claude-haiku-4-5-xxx
+	{"claude-opus-4-5", "claude-opus-4-5-thinking"},
+	{"claude-3-haiku", "gemini-3-flash"}, // 旧版 claude-3-haiku-xxx
+	{"claude-sonnet-4", "claude-sonnet-4-5"},
+	{"claude-haiku-4", "gemini-3-flash"},
+	{"claude-opus-4", "claude-opus-4-5-thinking"},
+	{"gemini-3-pro", "gemini-3-pro-high"}, // gemini-3-pro, gemini-3-pro-preview 等
 }
 
 // AntigravityGatewayService 处理 Antigravity 平台的 API 转发
@@ -84,24 +87,27 @@ func (s *AntigravityGatewayService) GetTokenProvider() *AntigravityTokenProvider
 }
 
 // getMappedModel 获取映射后的模型名
+// 逻辑：账户映射 → 直接支持透传 → 前缀映射 → gemini透传 → 默认值
 func (s *AntigravityGatewayService) getMappedModel(account *Account, requestedModel string) string {
-	// 1. 优先使用账户级映射（复用现有方法）
+	// 1. 账户级映射（用户自定义优先）
 	if mapped := account.GetMappedModel(requestedModel); mapped != requestedModel {
 		return mapped
 	}
 
-	// 2. 系统默认映射
-	if mapped, ok := antigravityModelMapping[requestedModel]; ok {
-		return mapped
-	}
-
-	// 3. Gemini 模型透传
-	if strings.HasPrefix(requestedModel, "gemini-") {
+	// 2. 直接支持的模型透传
+	if antigravitySupportedModels[requestedModel] {
 		return requestedModel
 	}
 
-	// 4. Claude 前缀透传直接支持的模型
-	if antigravitySupportedModels[requestedModel] {
+	// 3. 前缀映射（处理版本号变化，如 -20251111, -thinking, -preview）
+	for _, pm := range antigravityPrefixMapping {
+		if strings.HasPrefix(requestedModel, pm.prefix) {
+			return pm.target
+		}
+	}
+
+	// 4. Gemini 模型透传（未匹配到前缀的 gemini 模型）
+	if strings.HasPrefix(requestedModel, "gemini-") {
 		return requestedModel
 	}
 
@@ -110,24 +116,10 @@ func (s *AntigravityGatewayService) getMappedModel(account *Account, requestedMo
 }
 
 // IsModelSupported 检查模型是否被支持
+// 所有 claude- 和 gemini- 前缀的模型都能通过映射或透传支持
 func (s *AntigravityGatewayService) IsModelSupported(requestedModel string) bool {
-	// 直接支持的模型
-	if antigravitySupportedModels[requestedModel] {
-		return true
-	}
-	// 可映射的模型
-	if _, ok := antigravityModelMapping[requestedModel]; ok {
-		return true
-	}
-	// Gemini 前缀透传
-	if strings.HasPrefix(requestedModel, "gemini-") {
-		return true
-	}
-	// Claude 模型支持（通过默认映射）
-	if strings.HasPrefix(requestedModel, "claude-") {
-		return true
-	}
-	return false
+	return strings.HasPrefix(requestedModel, "claude-") ||
+		strings.HasPrefix(requestedModel, "gemini-")
 }
 
 // TestConnectionResult 测试连接结果
diff --git a/backend/internal/service/antigravity_model_mapping_test.go b/backend/internal/service/antigravity_model_mapping_test.go
index b3631dfc..1e37cdc2 100644
--- a/backend/internal/service/antigravity_model_mapping_test.go
+++ b/backend/internal/service/antigravity_model_mapping_test.go
@@ -131,7 +131,7 @@ func TestAntigravityGatewayService_GetMappedModel(t *testing.T) {
 			name:           "系统映射 - claude-sonnet-4-5-20250929",
 			requestedModel: "claude-sonnet-4-5-20250929",
 			accountMapping: nil,
-			expected:       "claude-sonnet-4-5-thinking",
+			expected:       "claude-sonnet-4-5",
 		},
 
 		// 3. Gemini 透传
diff --git a/backend/internal/service/gateway_service.go b/backend/internal/service/gateway_service.go
index cb60131b..1989ba78 100644
--- a/backend/internal/service/gateway_service.go
+++ b/backend/internal/service/gateway_service.go
@@ -893,24 +893,10 @@ func (s *GatewayService) isModelSupportedByAccount(account *Account, requestedMo
 }
 
 // IsAntigravityModelSupported 检查 Antigravity 平台是否支持指定模型
+// 所有 claude- 和 gemini- 前缀的模型都能通过映射或透传支持
 func IsAntigravityModelSupported(requestedModel string) bool {
-	// 直接支持的模型
-	if antigravitySupportedModels[requestedModel] {
-		return true
-	}
-	// 可映射的模型
-	if _, ok := antigravityModelMapping[requestedModel]; ok {
-		return true
-	}
-	// Gemini 前缀透传
-	if strings.HasPrefix(requestedModel, "gemini-") {
-		return true
-	}
-	// Claude 模型支持（通过默认映射到 claude-sonnet-4-5）
-	if strings.HasPrefix(requestedModel, "claude-") {
-		return true
-	}
-	return false
+	return strings.HasPrefix(requestedModel, "claude-") ||
+		strings.HasPrefix(requestedModel, "gemini-")
 }
 
 // GetAccessToken 获取账号凭证