diff --git a/AssetManager.Infrastructure/Services/MarketDataService.cs b/AssetManager.Infrastructure/Services/MarketDataService.cs
index d5e5206..a3427f4 100755
--- a/AssetManager.Infrastructure/Services/MarketDataService.cs
+++ b/AssetManager.Infrastructure/Services/MarketDataService.cs
@@ -20,6 +20,9 @@ public class MarketDataService : IMarketDataService
     private readonly ITiingoMarketService _tiingoService;
     private readonly IOkxMarketService _okxService;
     private readonly IMarketDataRepository _marketDataRepo;
+    
+    // 限制数据库并发访问，避免 SqlSugar 连接状态冲突
+    private static readonly SemaphoreSlim _dbSemaphore = new(3, 3);
 
     public MarketDataService(
         ILogger<MarketDataService> logger,
@@ -44,20 +47,29 @@ public class MarketDataService : IMarketDataService
     {
         _logger.LogInformation("获取实时价格: {Symbol}, 资产类型: {AssetType}", symbol, assetType);
         
-        // 先查缓存
-        var cached = await _marketDataRepo.GetPriceCacheAsync(symbol, assetType);
-        
-        if (cached != null)
+        // 限制数据库并发访问
+        await _dbSemaphore.WaitAsync();
+        try
         {
-            _logger.LogDebug("缓存命中: {Symbol} {AssetType}, 价格: {Price}", symbol, assetType, cached.Price);
-            return new MarketPriceResponse
+            // 先查缓存
+            var cached = await _marketDataRepo.GetPriceCacheAsync(symbol, assetType);
+        
+            if (cached != null)
             {
-                Symbol = cached.Symbol,
-                Price = cached.Price,
-                PreviousClose = cached.PreviousClose ?? 0,
-                Timestamp = cached.FetchedAt,
-                AssetType = cached.AssetType
-            };
+                _logger.LogDebug("缓存命中: {Symbol} {AssetType}, 价格: {Price}", symbol, assetType, cached.Price);
+                return new MarketPriceResponse
+                {
+                    Symbol = cached.Symbol,
+                    Price = cached.Price,
+                    PreviousClose = cached.PreviousClose ?? 0,
+                    Timestamp = cached.FetchedAt,
+                    AssetType = cached.AssetType
+                };
+            }
+        }
+        finally
+        {
+            _dbSemaphore.Release();
         }
 
         // 缓存未命中，调用API
@@ -108,8 +120,17 @@ public class MarketDataService : IMarketDataService
         _logger.LogInformation("获取历史数据: {Symbol}, 资产类型: {AssetType}, 周期: {Timeframe}, 数量: {Limit}", 
             symbol, assetType, timeframe, limit);
         
-        // 先查缓存
-        var cachedKlines = await _marketDataRepo.GetKlineCacheAsync(symbol, assetType, timeframe, limit);
+        // 限制数据库并发访问
+        await _dbSemaphore.WaitAsync();
+        List<MarketKlineCache> cachedKlines;
+        try
+        {
+            cachedKlines = await _marketDataRepo.GetKlineCacheAsync(symbol, assetType, timeframe, limit);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         
         // 缓存足够，直接返回
         if (cachedKlines.Count >= limit)
@@ -214,7 +235,15 @@ public class MarketDataService : IMarketDataService
             ExpiredAt = GetCacheExpirationTime(assetType)
         };
 
-        await _marketDataRepo.SavePriceCacheAsync(cacheEntity);
+        await _dbSemaphore.WaitAsync();
+        try
+        {
+            await _marketDataRepo.SavePriceCacheAsync(cacheEntity);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         _logger.LogDebug("缓存写入: {Symbol} {AssetType}, 过期时间: {ExpiredAt}", symbol, assetType, cacheEntity.ExpiredAt);
     }
 
@@ -235,7 +264,15 @@ public class MarketDataService : IMarketDataService
             FetchedAt = DateTime.Now
         }).ToList();
 
-        await _marketDataRepo.SaveKlineCacheBatchAsync(cacheEntities);
+        await _dbSemaphore.WaitAsync();
+        try
+        {
+            await _marketDataRepo.SaveKlineCacheBatchAsync(cacheEntities);
+        }
+        finally
+        {
+            _dbSemaphore.Release();
+        }
         _logger.LogDebug("历史K线缓存写入: {Symbol} {AssetType} {Timeframe}, 数量: {Count}", symbol, assetType, timeframe, cacheEntities.Count);
     }