diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5cfeb39d456..5679ebbcbe3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -245,6 +245,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Feishu/Streaming card text fidelity: merge throttled/fragmented partial updates without dropping content and avoid newline injection when stitching chunk-style deltas so card-stream output matches final reply text. (#29616) Thanks @HaoHuaqing.
 - Security/Feishu webhook ingress: bound unauthenticated webhook rate-limit state with stale-window pruning and a hard key cap to prevent unbounded pre-auth memory growth from rotating source keys. (#26050) Thanks @bmendonca3.
 - Security/Compaction audit: remove the post-compaction audit injection message. (#28507) Thanks @fuller-stack-dev and @vincentkoc.
 - Web tools/RFC2544 fake-IP compatibility: allow RFC2544 benchmark range (`198.18.0.0/15`) for trusted web-tool fetch endpoints so proxy fake-IP networking modes do not trigger false SSRF blocks. Landed from contributor PR #31176 by @sunkinux. Thanks @sunkinux.
diff --git a/extensions/feishu/src/streaming-card.test.ts b/extensions/feishu/src/streaming-card.test.ts
new file mode 100644
index 00000000000..913a4633ada
--- /dev/null
+++ b/extensions/feishu/src/streaming-card.test.ts
@@ -0,0 +1,18 @@
+import { describe, expect, it } from "vitest";
+import { mergeStreamingText } from "./streaming-card.js";
+
+describe("mergeStreamingText", () => {
+  it("prefers the latest full text when it already includes prior text", () => {
+    expect(mergeStreamingText("hello", "hello world")).toBe("hello world");
+  });
+
+  it("keeps previous text when the next partial is empty or redundant", () => {
+    expect(mergeStreamingText("hello", "")).toBe("hello");
+    expect(mergeStreamingText("hello world", "hello")).toBe("hello world");
+  });
+
+  it("appends fragmented chunks without injecting newlines", () => {
+    expect(mergeStreamingText("hello wor", "ld")).toBe("hello world");
+    expect(mergeStreamingText("line1", "line2")).toBe("line1line2");
+  });
+});
diff --git a/extensions/feishu/src/streaming-card.ts b/extensions/feishu/src/streaming-card.ts
index f67926f4eb4..615636467a9 100644
--- a/extensions/feishu/src/streaming-card.ts
+++ b/extensions/feishu/src/streaming-card.ts
@@ -85,6 +85,25 @@ function truncateSummary(text: string, max = 50): string {
   return clean.length <= max ? clean : clean.slice(0, max - 3) + "...";
 }
 
+export function mergeStreamingText(
+  previousText: string | undefined,
+  nextText: string | undefined,
+): string {
+  const previous = typeof previousText === "string" ? previousText : "";
+  const next = typeof nextText === "string" ? nextText : "";
+  if (!next) {
+    return previous;
+  }
+  if (!previous || next === previous || next.includes(previous)) {
+    return next;
+  }
+  if (previous.includes(next)) {
+    return previous;
+  }
+  // Fallback for fragmented partial chunks: append as-is to avoid losing tokens.
+  return `${previous}${next}`;
+}
+
 /** Streaming card session manager */
 export class FeishuStreamingSession {
   private client: Client;
@@ -235,10 +254,15 @@ export class FeishuStreamingSession {
     if (!this.state || this.closed) {
       return;
     }
+    const mergedInput = mergeStreamingText(this.pendingText ?? this.state.currentText, text);
+    if (!mergedInput || mergedInput === this.state.currentText) {
+      return;
+    }
+
     // Throttle: skip if updated recently, but remember pending text
     const now = Date.now();
     if (now - this.lastUpdateTime < this.updateThrottleMs) {
-      this.pendingText = text;
+      this.pendingText = mergedInput;
       return;
     }
     this.pendingText = null;
@@ -248,8 +272,12 @@ export class FeishuStreamingSession {
       if (!this.state || this.closed) {
         return;
       }
-      this.state.currentText = text;
-      await this.updateCardContent(text, (e) => this.log?.(`Update failed: ${String(e)}`));
+      const mergedText = mergeStreamingText(this.state.currentText, mergedInput);
+      if (!mergedText || mergedText === this.state.currentText) {
+        return;
+      }
+      this.state.currentText = mergedText;
+      await this.updateCardContent(mergedText, (e) => this.log?.(`Update failed: ${String(e)}`));
     });
     await this.queue;
   }
@@ -261,8 +289,8 @@ export class FeishuStreamingSession {
     this.closed = true;
     await this.queue;
 
-    // Use finalText, or pending throttled text, or current text
-    const text = finalText ?? this.pendingText ?? this.state.currentText;
+    const pendingMerged = mergeStreamingText(this.state.currentText, this.pendingText ?? undefined);
+    const text = finalText ? mergeStreamingText(pendingMerged, finalText) : pendingMerged;
     const apiBase = resolveApiBase(this.creds.domain);
 
     // Only send final update if content differs from what's already displayed