diff --git a/AssetManager.API/Controllers/PortfolioController.cs b/AssetManager.API/Controllers/PortfolioController.cs
index b6031ae..002f8d7 100644
--- a/AssetManager.API/Controllers/PortfolioController.cs
+++ b/AssetManager.API/Controllers/PortfolioController.cs
@@ -66,6 +66,51 @@ public class PortfolioController : ControllerBase
             }
 
             _logger.LogInformation("Request to create portfolio");
+
+            // 1. 获取用户默认币种
+            var db = _databaseService.GetDb();
+            var user = db.Queryable<User>().Where(u => u.Id == userId).First();
+            if (user == null)
+            {
+                return NotFound(new ApiResponse<CreatePortfolioResponse>
+                {
+                    code = AssetManager.Models.StatusCodes.NotFound,
+                    data = null,
+                    message = "用户不存在"
+                });
+            }
+
+            // 2. 校验组合币种，如果没传则用用户默认币种
+            if (string.IsNullOrEmpty(request.currency))
+            {
+                request.currency = user.DefaultCurrency;
+            }
+            if (!CurrencyHelper.IsSupported(request.currency))
+            {
+                return BadRequest(new ApiResponse<CreatePortfolioResponse>
+                {
+                    code = StatusCodes.BadRequest,
+                    data = null,
+                    message = $"不支持的组合币种: {request.currency}，支持的币种: {string.Join(", ", CurrencyHelper.GetSupportedCurrencies())}"
+                });
+            }
+
+            // 3. 校验持仓币种
+            if (request.stocks != null)
+            {
+                foreach (var stock in request.stocks)
+                {
+                    if (!string.IsNullOrEmpty(stock.currency) && !CurrencyHelper.IsSupported(stock.currency))
+                    {
+                        return BadRequest(new ApiResponse<CreatePortfolioResponse>
+                        {
+                            code = StatusCodes.BadRequest,
+                            data = null,
+                            message = $"不支持的持仓币种: {stock.currency}（标的: {stock.code}），支持的币种: {string.Join(", ", CurrencyHelper.GetSupportedCurrencies())}"
+                        });
+                    }
+                }
+            }
             
             var response = _portfolioService.CreatePortfolio(request, userId);
 
@@ -301,6 +346,32 @@ public class PortfolioController : ControllerBase
             }
 
             _logger.LogInformation("Request to create transaction");
+
+            // 校验交易币种
+            if (!string.IsNullOrEmpty(request.currency) && !CurrencyHelper.IsSupported(request.currency))
+            {
+                return BadRequest(new ApiResponse<CreateTransactionResponse>
+                {
+                    code = StatusCodes.BadRequest,
+                    data = null,
+                    message = $"不支持的交易币种: {request.currency}，支持的币种: {string.Join(", ", CurrencyHelper.GetSupportedCurrencies())}"
+                });
+            }
+
+            // 校验资产类型
+            if (!string.IsNullOrEmpty(request.assetType))
+            {
+                var validAssetTypes = new[] { "Stock", "Crypto" };
+                if (!validAssetTypes.Contains(request.assetType, StringComparer.OrdinalIgnoreCase))
+                {
+                    return BadRequest(new ApiResponse<CreateTransactionResponse>
+                    {
+                        code = StatusCodes.BadRequest,
+                        data = null,
+                        message = $"不支持的资产类型: {request.assetType}，支持的类型: {string.Join(", ", validAssetTypes)}"
+                    });
+                }
+            }
             
             var response = _portfolioService.CreateTransaction(request, userId);
 
diff --git a/AssetManager.API/Controllers/UserController.cs b/AssetManager.API/Controllers/UserController.cs
index 4c2f0f7..4937b40 100644
--- a/AssetManager.API/Controllers/UserController.cs
+++ b/AssetManager.API/Controllers/UserController.cs
@@ -68,7 +68,8 @@ public class UserController : ControllerBase
                 MemberLevel = user.MemberLevel,
                 RunningDays = user.RunningDays,
                 Avatar = user.Avatar,
-                Email = user.Email
+                Email = user.Email,
+                DefaultCurrency = user.DefaultCurrency
             };
 
             _logger.LogInformation("User info retrieved successfully");
@@ -206,8 +207,22 @@ public class UserController : ControllerBase
                 });
             }
             
+            // 校验币种
+            if (!string.IsNullOrEmpty(request.DefaultCurrency) && !CurrencyHelper.IsSupported(request.DefaultCurrency))
+            {
+                return BadRequest(new ApiResponse<UpdateUserResponse>
+                {
+                    code = StatusCodes.BadRequest,
+                    data = null,
+                    message = $"不支持的币种: {request.DefaultCurrency}，支持的币种: {string.Join(", ", CurrencyHelper.GetSupportedCurrencies())}"
+                });
+            }
+
             // 更新用户信息
             user.UserName = request.UserName;
+            if (!string.IsNullOrEmpty(request.Avatar)) user.Avatar = request.Avatar;
+            if (!string.IsNullOrEmpty(request.Email)) user.Email = request.Email;
+            if (!string.IsNullOrEmpty(request.DefaultCurrency)) user.DefaultCurrency = request.DefaultCurrency;
             user.UpdatedAt = DateTime.Now;
             db.Updateable(user).ExecuteCommand();
             
diff --git a/AssetManager.Data/User.cs b/AssetManager.Data/User.cs
index 7a3498d..dae2e17 100644
--- a/AssetManager.Data/User.cs
+++ b/AssetManager.Data/User.cs
@@ -43,6 +43,12 @@ public class User
     /// </summary>
     [SugarColumn(ColumnName = "member_level", Length = 50)]
     public string MemberLevel { get; set; }
+
+    /// <summary>
+    /// 用户默认本位币 (CNY/USD/HKD)
+    /// </summary>
+    [SugarColumn(ColumnName = "default_currency", Length = 10)]
+    public string DefaultCurrency { get; set; } = "CNY";
     
     /// <summary>
     /// 连续运行天数
diff --git a/AssetManager.Models/Currency.cs b/AssetManager.Models/Currency.cs
new file mode 100644
index 0000000..ffe88af
--- /dev/null
+++ b/AssetManager.Models/Currency.cs
@@ -0,0 +1,49 @@
+namespace AssetManager.Models;
+
+/// <summary>
+/// 支持的币种枚举
+/// </summary>
+public enum Currency
+{
+    /// <summary>
+    /// 人民币
+    /// </summary>
+    CNY = 0,
+
+    /// <summary>
+    /// 美元
+    /// </summary>
+    USD = 1,
+
+    /// <summary>
+    /// 港币
+    /// </summary>
+    HKD = 2
+}
+
+/// <summary>
+/// 币种辅助类
+/// </summary>
+public static class CurrencyHelper
+{
+    private static readonly HashSet<string> _supportedCurrencies = new(StringComparer.OrdinalIgnoreCase)
+    {
+        "CNY", "USD", "HKD"
+    };
+
+    /// <summary>
+    /// 检查币种是否支持
+    /// </summary>
+    public static bool IsSupported(string currency)
+    {
+        return !string.IsNullOrEmpty(currency) && _supportedCurrencies.Contains(currency);
+    }
+
+    /// <summary>
+    /// 获取支持的币种列表
+    /// </summary>
+    public static List<string> GetSupportedCurrencies()
+    {
+        return new List<string> { "CNY", "USD", "HKD" };
+    }
+}
diff --git a/AssetManager.Models/DTOs/UserDTO.cs b/AssetManager.Models/DTOs/UserDTO.cs
index 0571c7c..09d800a 100644
--- a/AssetManager.Models/DTOs/UserDTO.cs
+++ b/AssetManager.Models/DTOs/UserDTO.cs
@@ -7,6 +7,15 @@ public class UserInfoResponse
     public int RunningDays { get; set; }
     public string Avatar { get; set; }
     public string Email { get; set; }
+    public string DefaultCurrency { get; set; }
+}
+
+public class UpdateUserRequest
+{
+    public string UserName { get; set; }
+    public string Avatar { get; set; }
+    public string Email { get; set; }
+    public string DefaultCurrency { get; set; }
 }
 
 public class UserStatsResponse