diff --git a/backend/internal/service/billing_service.go b/backend/internal/service/billing_service.go
index a45203a3..392b3e0b 100644
--- a/backend/internal/service/billing_service.go
+++ b/backend/internal/service/billing_service.go
@@ -217,6 +217,9 @@ func (s *BillingService) initFallbackPricing() {
 		LongContextInputMultiplier:     openAIGPT54LongContextInputMultiplier,
 		LongContextOutputMultiplier:    openAIGPT54LongContextOutputMultiplier,
 	}
+	// GPT-5.5 暂无独立定价，回退到 GPT-5.4
+	s.fallbackPrices["gpt-5.5"] = s.fallbackPrices["gpt-5.4"]
+
 	s.fallbackPrices["gpt-5.4-mini"] = &ModelPricing{
 		InputPricePerToken:     7.5e-7,
 		OutputPricePerToken:    4.5e-6,
@@ -288,6 +291,8 @@ func (s *BillingService) getFallbackPricing(model string) *ModelPricing {
 	if strings.Contains(modelLower, "gpt-5") || strings.Contains(modelLower, "codex") {
 		normalized := normalizeCodexModel(modelLower)
 		switch normalized {
+		case "gpt-5.5":
+			return s.fallbackPrices["gpt-5.5"]
 		case "gpt-5.4-mini":
 			return s.fallbackPrices["gpt-5.4-mini"]
 		case "gpt-5.4":
@@ -637,7 +642,8 @@ func isOpenAIGPT54Model(model string) bool {
 	if !strings.Contains(trimmed, "gpt-5") && !strings.Contains(trimmed, "codex") {
 		return false
 	}
-	return normalizeCodexModel(trimmed) == "gpt-5.4"
+	normalized := normalizeCodexModel(trimmed)
+	return normalized == "gpt-5.4" || normalized == "gpt-5.5"
 }
 
 // CalculateCostWithConfig 使用配置中的默认倍率计算费用
diff --git a/backend/internal/service/openai_codex_transform.go b/backend/internal/service/openai_codex_transform.go
index a68c9b67..560db436 100644
--- a/backend/internal/service/openai_codex_transform.go
+++ b/backend/internal/service/openai_codex_transform.go
@@ -6,6 +6,7 @@ import (
 )
 
 var codexModelMap = map[string]string{
+	"gpt-5.5":                    "gpt-5.5",
 	"gpt-5.4":                    "gpt-5.4",
 	"gpt-5.4-mini":               "gpt-5.4-mini",
 	"gpt-5.4-none":               "gpt-5.4",
@@ -207,6 +208,9 @@ func normalizeCodexModel(model string) string {
 
 	normalized := strings.ToLower(modelID)
 
+	if strings.Contains(normalized, "gpt-5.5") || strings.Contains(normalized, "gpt 5.5") {
+		return "gpt-5.5"
+	}
 	if strings.Contains(normalized, "gpt-5.4-mini") || strings.Contains(normalized, "gpt 5.4 mini") {
 		return "gpt-5.4-mini"
 	}
diff --git a/backend/internal/service/pricing_service.go b/backend/internal/service/pricing_service.go
index 106ec9f7..91a02901 100644
--- a/backend/internal/service/pricing_service.go
+++ b/backend/internal/service/pricing_service.go
@@ -794,6 +794,13 @@ func (s *PricingService) matchOpenAIModel(model string) *LiteLLMModelPricing {
 		}
 	}
 
+	// GPT-5.5 回退到 GPT-5.4 定价
+	if strings.HasPrefix(model, "gpt-5.5") {
+		logger.With(zap.String("component", "service.pricing")).
+			Info(fmt.Sprintf("[Pricing] OpenAI fallback matched %s -> %s", model, "gpt-5.4(static)"))
+		return openAIGPT54FallbackPricing
+	}
+
 	if strings.HasPrefix(model, "gpt-5.4-mini") {
 		logger.With(zap.String("component", "service.pricing")).
 			Info(fmt.Sprintf("[Pricing] OpenAI fallback matched %s -> %s", model, "gpt-5.4-mini(static)"))
diff --git a/frontend/src/components/keys/UseKeyModal.vue b/frontend/src/components/keys/UseKeyModal.vue
index b3679107..94010b62 100644
--- a/frontend/src/components/keys/UseKeyModal.vue
+++ b/frontend/src/components/keys/UseKeyModal.vue
@@ -633,6 +633,22 @@ function generateOpenCodeConfig(platform: string, baseUrl: string, apiKey: strin
         xhigh: {}
       }
     },
+    'gpt-5.5': {
+      name: 'GPT-5.5',
+      limit: {
+        context: 1050000,
+        output: 128000
+      },
+      options: {
+        store: false
+      },
+      variants: {
+        low: {},
+        medium: {},
+        high: {},
+        xhigh: {}
+      }
+    },
     'gpt-5.4': {
       name: 'GPT-5.4',
       limit: {
diff --git a/frontend/src/composables/useModelWhitelist.ts b/frontend/src/composables/useModelWhitelist.ts
index 71b1e9b3..a8b77b23 100644
--- a/frontend/src/composables/useModelWhitelist.ts
+++ b/frontend/src/composables/useModelWhitelist.ts
@@ -16,6 +16,8 @@ const openaiModels = [
   // GPT-5.2 系列
   'gpt-5.2', 'gpt-5.2-2025-12-11', 'gpt-5.2-chat-latest',
   'gpt-5.2-pro', 'gpt-5.2-pro-2025-12-11',
+  // GPT-5.5 系列
+  'gpt-5.5',
   // GPT-5.4 系列
   'gpt-5.4', 'gpt-5.4-mini', 'gpt-5.4-2026-03-05',
   // GPT-5.3 系列
@@ -260,6 +262,7 @@ const openaiPresetMappings = [
   { label: 'o3', from: 'o3', to: 'o3', color: 'bg-emerald-100 text-emerald-700 hover:bg-emerald-200 dark:bg-emerald-900/30 dark:text-emerald-400' },
   { label: 'GPT-5.3 Codex Spark', from: 'gpt-5.3-codex-spark', to: 'gpt-5.3-codex-spark', color: 'bg-teal-100 text-teal-700 hover:bg-teal-200 dark:bg-teal-900/30 dark:text-teal-400' },
   { label: 'GPT-5.2', from: 'gpt-5.2', to: 'gpt-5.2', color: 'bg-red-100 text-red-700 hover:bg-red-200 dark:bg-red-900/30 dark:text-red-400' },
+  { label: 'GPT-5.5', from: 'gpt-5.5', to: 'gpt-5.5', color: 'bg-amber-100 text-amber-700 hover:bg-amber-200 dark:bg-amber-900/30 dark:text-amber-400' },
   { label: 'GPT-5.4', from: 'gpt-5.4', to: 'gpt-5.4', color: 'bg-rose-100 text-rose-700 hover:bg-rose-200 dark:bg-rose-900/30 dark:text-rose-400' },
   { label: 'Haiku→5.4', from: 'claude-haiku-4-5-20251001', to: 'gpt-5.4', color: 'bg-emerald-100 text-emerald-700 hover:bg-emerald-200 dark:bg-emerald-900/30 dark:text-emerald-400' },
   { label: 'Opus→5.4', from: 'claude-opus-4-6', to: 'gpt-5.4', color: 'bg-purple-100 text-purple-700 hover:bg-purple-200 dark:bg-purple-900/30 dark:text-purple-400' },