diff --git a/backend/cmd/main.go b/backend/cmd/main.go
index 820646d..967a175 100755
--- a/backend/cmd/main.go
+++ b/backend/cmd/main.go
@@ -25,7 +25,7 @@ func main() {
 	gin.SetMode(cfg.Server.Mode)
 
 	// 初始化 SQLite 数据库
-	if err := db.Init(cfg.Database.DSN, &model.User{}, &model.Project{}, &model.ProjectStyleRecord{}, &model.Task{}); err != nil {
+	if err := db.Init(cfg.Database.DSN, &model.User{}, &model.Project{}, &model.ProjectStyleRecord{}, &model.Task{}, &model.Asset{}); err != nil {
 		slog.Error("db init failed", "error", err)
 		return
 	}
diff --git a/backend/internal/handler/generate.go b/backend/internal/handler/generate.go
index 7ec2df0..0c5864b 100755
--- a/backend/internal/handler/generate.go
+++ b/backend/internal/handler/generate.go
@@ -2,11 +2,13 @@ package handler
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"net/http"
-	"sync"
+	"strconv"
 	"time"
 
+	"gen2d/internal/db"
 	"gen2d/internal/logger"
 	"gen2d/internal/model"
 	"gen2d/internal/service"
@@ -34,44 +36,12 @@ type GenerateResponse struct {
 	TaskID string `json:"taskId"`
 }
 
-// AssetResponse 单个素材响应。
-type AssetResponse struct {
-	Key    string `json:"key"`
-	URL    string `json:"url"`
-	Format string `json:"format"`
-}
-
-// TaskResponse 任务查询响应。
-type TaskResponse struct {
-	ID         string `json:"id"`
-	ProjectID  string `json:"projectId"`
-	Prompt     string `json:"prompt"`
-	AssetType  string `json:"assetType"`
-	Status     string `json:"status"`
-	Stage      string `json:"stage,omitempty"`
-	Progress   int    `json:"progress"`
-	RetryCount int    `json:"retryCount"`
-	Error      string `json:"error,omitempty"`
-	CreatedAt  string `json:"createdAt"`
-}
-
 // AssetsResponse 素材列表响应。
 type AssetsResponse struct {
-	Assets   []AssetResponse       `json:"assets"`
+	Assets   []model.AssetResponse       `json:"assets"`
 	Metadata service.AssetMetadata `json:"metadata"`
 }
 
-// taskRecord 内存中的任务记录。
-type taskRecord struct {
-	task     TaskResponse
-	assets   []AssetResponse
-	metadata service.AssetMetadata
-}
-
-var (
-	taskStore = sync.Map{} // taskID → *taskRecord
-)
-
 // Generate 素材生成接口（异步）。
 // 立即返回 taskId，后台执行管线，前端通过 GET /tasks/:taskId 轮询进度。
 func Generate(c *gin.Context) {
@@ -86,38 +56,31 @@ func Generate(c *gin.Context) {
 		projectID = "default"
 	}
 	taskID := fmt.Sprintf("task-%d", time.Now().UnixMilli())
-	createdAt := time.Now().Format(time.RFC3339)
 
-	// 存入 pending 状态
-	taskStore.Store(taskID, &taskRecord{
-		task: TaskResponse{
-			ID:        taskID,
-			ProjectID: projectID,
-			Prompt:    req.Prompt,
-			AssetType: req.AssetType,
-			Status:    "pending",
-			Progress:  0,
-			CreatedAt: createdAt,
-		},
-	})
+	// 保存任务到数据库
+	if err := saveTaskToDB(c.Request.Context(), projectID, taskID, req); err != nil {
+		logger.FromCtx(c.Request.Context()).Error("failed to save task", "error", err)
+		c.JSON(http.StatusInternalServerError, model.Fail(http.StatusInternalServerError, "创建任务失败"))
+		return
+	}
 
 	// 返回 taskId
 	c.JSON(http.StatusOK, model.OK(GenerateResponse{TaskID: taskID}))
 
 	// 后台执行管线
-	go runPipelineBg(projectID, taskID, req)
+	go runPipelineBg(c.Request.Context(), projectID, taskID, req)
 }
 
 // runPipelineBg 后台执行生成管线，更新任务状态。
-func runPipelineBg(projectID, taskID string, req GenerateRequest) {
-	// 注入进度上报回调
-	ctx := service.WithProgressReporter(context.Background(), func(stage string, progress int) {
-		updateTaskProgress(taskID, "running", stage, progress)
-	})
-
+func runPipelineBg(ctx context.Context, projectID, taskID string, req GenerateRequest) {
 	l := logger.With("task_id", taskID, "project_id", projectID)
 
-	updateTaskProgress(taskID, "running", "prompt_builder", 5)
+	// 注入进度上报回调
+	ctx = service.WithProgressReporter(ctx, func(stage string, progress int) {
+		updateTaskInDB(ctx, taskID, "running", stage, "", progress)
+	})
+
+	updateTaskInDB(ctx, taskID, "running", "prompt_builder", "", 5)
 
 	in := service.PipelineInput{
 		ProjectID:    projectID,
@@ -141,96 +104,187 @@ func runPipelineBg(projectID, taskID string, req GenerateRequest) {
 	output, err := service.RunPipeline(ctx, in)
 	if err != nil {
 		l.Error("task pipeline failed", "error", err)
-		updateFailed(taskID, "生成管线执行失败")
+		updateTaskInDB(ctx, taskID, "failed", "", err.Error(), 0)
 		return
 	}
 
-	updateTaskProgress(taskID, "saving", "format_adapter", 90)
+	updateTaskInDB(ctx, taskID, "saving", "format_adapter", "", 90)
 
-	assets := make([]AssetResponse, len(output.Assets))
+	// 上传素材并保存到数据库
 	for i, a := range output.Assets {
 		key := fmt.Sprintf("generation/%s/%s/%d.%s", projectID, taskID, i, a.Format)
 		cdnURL, err := storageSvc.Upload(ctx, key, a.Data)
 		if err != nil {
 			l.Error("upload asset failed", "index", i, "error", err)
-			updateFailed(taskID, "上传素材失败")
+			updateTaskInDB(ctx, taskID, "failed", "", "上传素材失败: "+err.Error(), 0)
 			return
 		}
-		assets[i] = AssetResponse{
-			Key:    key,
-			URL:    cdnURL,
-			Format: a.Format,
+
+		// 序列化单个素材的元数据
+		var metadata map[string]interface{}
+		if i < len(output.Assets) {
+			metadata = map[string]interface{}{
+				"index": i,
+			}
+		}
+		metadataJSON, _ := json.Marshal(metadata)
+
+		asset := &model.Asset{
+			TaskID:   getTaskDBID(ctx, taskID),
+			Key:      key,
+			URL:      cdnURL,
+			Format:   a.Format,
+			Metadata: string(metadataJSON),
+		}
+
+		if err := db.GetDB().WithContext(ctx).Create(asset).Error; err != nil {
+			l.Error("save asset to db failed", "index", i, "error", err)
 		}
 	}
 
 	// 更新为完成状态
-	taskStore.Store(taskID, &taskRecord{
-		task: TaskResponse{
-			ID:        taskID,
-			ProjectID: projectID,
-			Prompt:    req.Prompt,
-			AssetType: req.AssetType,
-			Status:    "completed",
-			Progress:  100,
-			CreatedAt: time.Now().Format(time.RFC3339),
-		},
-		assets:   assets,
-		metadata: output.Metadata,
-	})
-
-	l.Info("task completed", "asset_count", len(assets))
-}
-
-func updateTaskProgress(taskID, status, stage string, progress int) {
-	rec, ok := taskStore.Load(taskID)
-	if !ok {
-		return
+	var fullMetadata string
+	if metadataJSON, err := json.Marshal(output.Metadata); err == nil {
+		fullMetadata = string(metadataJSON)
 	}
-	r := rec.(*taskRecord)
-	r.task.Status = status
-	r.task.Stage = stage
-	r.task.Progress = progress
-	taskStore.Store(taskID, r)
-}
 
-func updateFailed(taskID, errMsg string) {
-	rec, ok := taskStore.Load(taskID)
-	if !ok {
-		return
-	}
-	r := rec.(*taskRecord)
-	r.task.Status = "failed"
-	r.task.Error = errMsg
-	taskStore.Store(taskID, r)
+	db.GetDB().WithContext(ctx).Model(&model.Task{}).
+		Where("external_id = ?", taskID).
+		Updates(map[string]interface{}{
+			"status":   "completed",
+			"progress": 100,
+			"metadata": fullMetadata,
+		})
+
+	l.Info("task completed")
 }
 
 // GetTask 查询任务信息。
 func GetTask(c *gin.Context) {
 	taskID := c.Param("taskId")
-	rec, ok := taskStore.Load(taskID)
-	if !ok {
+
+	var task model.Task
+	if err := db.GetDB().WithContext(c.Request.Context()).
+		Where("external_id = ?", taskID).
+		First(&task).Error; err != nil {
 		c.JSON(http.StatusNotFound, model.Fail(http.StatusNotFound, "任务不存在"))
 		return
 	}
-	r := rec.(*taskRecord)
-	c.JSON(http.StatusOK, model.OK(r.task))
+
+	c.JSON(http.StatusOK, model.OK(toTaskResponse(&task)))
 }
 
 // GetAssets 查询任务素材列表。
 func GetAssets(c *gin.Context) {
 	taskID := c.Param("taskId")
-	rec, ok := taskStore.Load(taskID)
-	if !ok {
+
+	var task model.Task
+	if err := db.GetDB().WithContext(c.Request.Context()).
+		Where("external_id = ?", taskID).
+		First(&task).Error; err != nil {
 		c.JSON(http.StatusNotFound, model.Fail(http.StatusNotFound, "任务不存在"))
 		return
 	}
-	r := rec.(*taskRecord)
-	if r.task.Status != "completed" {
-		c.JSON(http.StatusBadRequest, model.Fail(http.StatusBadRequest, "任务尚未完成，当前状态: "+r.task.Status))
+
+	if task.Status != "completed" {
+		c.JSON(http.StatusBadRequest, model.Fail(http.StatusBadRequest, "任务尚未完成，当前状态: "+task.Status))
 		return
 	}
+
+	var assets []model.Asset
+	if err := db.GetDB().WithContext(c.Request.Context()).
+		Where("task_id = ?", task.ID).
+		Find(&assets).Error; err != nil {
+		c.JSON(http.StatusInternalServerError, model.Fail(http.StatusInternalServerError, "查询素材失败"))
+		return
+	}
+
+	response := []model.AssetResponse{}
+	for _, a := range assets {
+		response = append(response, model.AssetResponse{
+			Key:    a.Key,
+			URL:    a.URL,
+			Format: a.Format,
+		})
+	}
+
+	var metadata service.AssetMetadata
+	if task.Metadata != "" {
+		json.Unmarshal([]byte(task.Metadata), &metadata)
+	}
+
 	c.JSON(http.StatusOK, model.OK(AssetsResponse{
-		Assets:   r.assets,
-		Metadata: r.metadata,
+		Assets:   response,
+		Metadata: metadata,
 	}))
 }
+
+// saveTaskToDB 将任务记录保存到数据库。
+func saveTaskToDB(ctx context.Context, projectID, taskID string, req GenerateRequest) error {
+	// "default" 工程没有数据库记录，跳过
+	if projectID == "default" {
+		return nil
+	}
+
+	projectIDUint, err := strconv.ParseUint(projectID, 10, 32)
+	if err != nil {
+		return fmt.Errorf("failed to parse projectID: %w", err)
+	}
+
+	task := &model.Task{
+		ExternalID: taskID,
+		ProjectID:  uint(projectIDUint),
+		Prompt:     req.Prompt,
+		AssetType:  req.AssetType,
+		Status:     "pending",
+		Progress:   0,
+		RetryCount: 0,
+		CreatedAt:  time.Now(),
+		UpdatedAt:  time.Now(),
+	}
+
+	return db.GetDB().WithContext(ctx).Create(task).Error
+}
+
+// updateTaskInDB 更新数据库中的任务状态。
+func updateTaskInDB(ctx context.Context, taskID, status, stage, error string, progress int) {
+	updates := map[string]interface{}{
+		"status":   status,
+		"progress": progress,
+		"updated_at": time.Now(),
+	}
+	if stage != "" {
+		updates["stage"] = stage
+	}
+	if error != "" {
+		updates["error"] = error
+	}
+
+	db.GetDB().WithContext(ctx).Model(&model.Task{}).
+		Where("external_id = ?", taskID).
+		Updates(updates)
+}
+
+// getTaskDBID 根据外部taskID获取数据库中的任务ID。
+func getTaskDBID(ctx context.Context, taskID string) uint {
+	var task model.Task
+	db.GetDB().WithContext(ctx).Select("id").Where("external_id = ?", taskID).First(&task)
+	return task.ID
+}
+
+// toTaskResponse 转换任务响应格式。
+func toTaskResponse(task *model.Task) model.TaskResponse {
+	return model.TaskResponse{
+		ID:         task.ExternalID,
+		ProjectID:  fmt.Sprintf("%d", task.ProjectID),
+		Prompt:     task.Prompt,
+		AssetType:  task.AssetType,
+		Status:     task.Status,
+		Stage:      task.Stage,
+		Progress:   task.Progress,
+		RetryCount: task.RetryCount,
+		Error:      task.Error,
+		CreatedAt:  task.CreatedAt.Format("2006-01-02T15:04:05Z07:00"),
+		UpdatedAt:  task.UpdatedAt.Format("2006-01-02T15:04:05Z07:00"),
+	}
+}
diff --git a/backend/internal/model/asset.go b/backend/internal/model/asset.go
new file mode 100644
index 0000000..c9c12b1
--- /dev/null
+++ b/backend/internal/model/asset.go
@@ -0,0 +1,22 @@
+package model
+
+import "time"
+
+// Asset 素材数据模型，对应数据库表。
+type Asset struct {
+	ID        uint      `gorm:"primaryKey"`
+	TaskID    uint      `gorm:"index;not null"`
+	Key       string    `gorm:"size:255;not null"`         // 七牛云对象键
+	URL       string    `gorm:"size:255;not null"`         // CDN访问URL
+	Format    string    `gorm:"size:20;not null"`          // 文件格式
+	Metadata  string    `gorm:"type:text"`                 // 元数据（JSON格式）
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}
+
+// AssetResponse 素材响应。
+type AssetResponse struct {
+	Key    string `json:"key"`
+	URL    string `json:"url"`
+	Format string `json:"format"`
+}
diff --git a/backend/internal/model/task.go b/backend/internal/model/task.go
index a62ab60..a2160d0 100644
--- a/backend/internal/model/task.go
+++ b/backend/internal/model/task.go
@@ -4,15 +4,17 @@ import "time"
 
 // Task 任务数据模型，对应数据库表。
 type Task struct {
-	ID         uint      `gorm:"primaryKey" json:"id"`
-	ProjectID  uint      `gorm:"index" json:"-"`
-	Prompt     string    `gorm:"type:text" json:"prompt"`
-	AssetType  string    `gorm:"size:50" json:"assetType"`
-	Status     string    `gorm:"size:20;default:'pending'" json:"status"`
-	Stage      string    `gorm:"size:50" json:"stage,omitempty"`
-	Progress   int       `gorm:"default:0" json:"progress"`
-	RetryCount int       `gorm:"default:0" json:"retryCount"`
-	Error      string    `gorm:"type:text" json:"error,omitempty"`
+	ID         uint   `gorm:"primaryKey" json:"id"`
+	ExternalID string `gorm:"size:100;index" json:"externalId,omitempty"` // 外部任务ID，关联taskID
+	ProjectID  uint   `gorm:"index" json:"-"`
+	Prompt     string `gorm:"type:text" json:"prompt"`
+	AssetType  string `gorm:"size:50" json:"assetType"`
+	Status     string `gorm:"size:20;default:'pending'" json:"status"`
+	Stage      string `gorm:"size:50" json:"stage,omitempty"`
+	Progress   int    `gorm:"default:0" json:"progress"`
+	RetryCount int    `gorm:"default:0" json:"retryCount"`
+	Error      string `gorm:"type:text" json:"error,omitempty"`
+	Metadata   string `gorm:"type:text" json:"-"` // 元数据（JSON格式）
 	CreatedAt  time.Time `json:"createdAt"`
 	UpdatedAt  time.Time `json:"updatedAt,omitempty"`
 }