diff --git a/mateclaw-server/src/main/java/vip/mate/tool/image/ImageFileDownloader.java b/mateclaw-server/src/main/java/vip/mate/tool/image/ImageFileDownloader.java
index 02964ef1..b008e4d1 100644
--- a/mateclaw-server/src/main/java/vip/mate/tool/image/ImageFileDownloader.java
+++ b/mateclaw-server/src/main/java/vip/mate/tool/image/ImageFileDownloader.java
@@ -5,6 +5,8 @@ import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Component;
 
 import java.io.IOException;
+import java.net.URLDecoder;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -22,12 +24,27 @@ public class ImageFileDownloader {
     private static final Path UPLOAD_ROOT = Paths.get("data", "chat-uploads");
 
     /**
-     * 从 URL 下载图片到本地
+     * Persist an image referenced by either a {@code data:} URL (inline base64 /
+     * percent-encoded payload) or an http(s) CDN URL. Returns the local path
+     * the caller can convert to a serving URL via {@link #toServingUrl}.
+     *
+     * <p>Without the {@code data:} branch, callers ended up handing the raw URL
+     * to {@code HttpUtil.downloadFile}, which interprets it relative to the
+     * working directory and produces nonsense like
+     * {@code file:/cwd/http:/data:image/...} before failing — the image never
+     * lands on disk and the assistant message renders empty.
      */
     public Path download(String imageUrl, String conversationId, String taskId, int index) throws IOException {
+        if (imageUrl == null) {
+            throw new IOException("imageUrl is null");
+        }
         Path dir = UPLOAD_ROOT.resolve(conversationId);
         Files.createDirectories(dir);
 
+        if (imageUrl.startsWith("data:")) {
+            return saveDataUrl(imageUrl, dir, taskId, index);
+        }
+
         String extension = guessExtension(imageUrl);
         String fileName = "image_" + taskId + "_" + index + extension;
         Path targetFile = dir.resolve(fileName);
@@ -39,6 +56,56 @@ public class ImageFileDownloader {
         return targetFile;
     }
 
+    /**
+     * Decode a {@code data:[<mediatype>][;base64],<data>} URL onto disk.
+     * Handles both the base64-encoded and percent-encoded body forms defined
+     * by RFC 2397, and picks the file extension from the media type so the
+     * stored asset is openable by name.
+     */
+    private Path saveDataUrl(String dataUrl, Path dir, String taskId, int index) throws IOException {
+        int comma = dataUrl.indexOf(',');
+        if (comma < 0) {
+            throw new IOException("Malformed data URL: missing comma");
+        }
+        // Header layout: "data:<mediatype>?(;base64)?"  (we already saw "data:")
+        String header = dataUrl.substring("data:".length(), comma);
+        String body = dataUrl.substring(comma + 1);
+
+        boolean isBase64 = header.toLowerCase().contains(";base64");
+        String mime = isBase64
+                ? header.substring(0, header.toLowerCase().indexOf(";base64"))
+                : (header.indexOf(';') >= 0 ? header.substring(0, header.indexOf(';')) : header);
+
+        byte[] bytes;
+        try {
+            bytes = isBase64
+                    ? Base64.getDecoder().decode(body)
+                    : URLDecoder.decode(body, StandardCharsets.UTF_8).getBytes(StandardCharsets.UTF_8);
+        } catch (IllegalArgumentException e) {
+            throw new IOException("Invalid base64 payload in data URL: " + e.getMessage(), e);
+        }
+
+        String extension = extensionForMime(mime);
+        String fileName = "image_" + taskId + "_" + index + extension;
+        Path targetFile = dir.resolve(fileName);
+        Files.write(targetFile, bytes);
+        log.info("[ImageDownloader] Saved data URL ({} bytes, mime={}) to {}",
+                bytes.length, mime.isBlank() ? "image/png" : mime, targetFile);
+        return targetFile;
+    }
+
+    private static String extensionForMime(String mime) {
+        if (mime == null) return ".png";
+        return switch (mime.toLowerCase().trim()) {
+            case "image/jpeg", "image/jpg" -> ".jpg";
+            case "image/webp" -> ".webp";
+            case "image/gif" -> ".gif";
+            case "image/bmp" -> ".bmp";
+            case "image/svg+xml" -> ".svg";
+            default -> ".png";
+        };
+    }
+
     /**
      * 将 Base64 编码的图片保存到本地
      */
diff --git a/mateclaw-server/src/main/java/vip/mate/tool/image/ImageGenerationService.java b/mateclaw-server/src/main/java/vip/mate/tool/image/ImageGenerationService.java
index 282c1154..44751781 100644
--- a/mateclaw-server/src/main/java/vip/mate/tool/image/ImageGenerationService.java
+++ b/mateclaw-server/src/main/java/vip/mate/tool/image/ImageGenerationService.java
@@ -4,6 +4,7 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.stereotype.Service;
+import vip.mate.channel.web.ChatStreamTracker;
 import vip.mate.system.model.SystemSettingsDTO;
 import vip.mate.system.service.SystemSettingService;
 import vip.mate.task.AsyncTaskService;
@@ -15,7 +16,9 @@ import vip.mate.workspace.conversation.model.MessageContentPart;
 
 import java.nio.file.Path;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 /**
  * 图片生成服务 — 统一入口，处理 provider 选择、参数归一化、fallback、同步/异步提交
@@ -35,6 +38,7 @@ public class ImageGenerationService {
     private final ConversationService conversationService;
     private final ImageFileDownloader fileDownloader;
     private final ObjectMapper objectMapper;
+    private final ChatStreamTracker streamTracker;
 
     private static final String TASK_TYPE = "image_generation";
 
@@ -186,6 +190,23 @@ public class ImageGenerationService {
                     "图片已生成完毕",
                     contentParts, "completed");
 
+            // Broadcast async_task_completed so the chat window renders the image
+            // inline immediately. Without this, the message is in DB but the SSE
+            // stream never tells the frontend a new assistant turn arrived, so the
+            // user's "loading…" spinner stays until they refresh and the
+            // conversation re-fetches from DB. Mirror the async path's payload
+            // shape (taskId / taskType / success / imageUrl) so the existing
+            // frontend handler treats it identically.
+            for (String servingUrl : servingUrls) {
+                Map<String, Object> data = new HashMap<>();
+                data.put("taskId", taskId);
+                data.put("taskType", TASK_TYPE);
+                data.put("success", true);
+                data.put("imageUrl", servingUrl);
+                data.put("providerName", submitResult.getProviderName());
+                streamTracker.broadcastObject(conversationId, "async_task_completed", data);
+            }
+
             log.info("[ImageGen] Sync generation completed, {} image(s) saved for conversation {}",
                     servingUrls.size(), conversationId);