diff --git a/agents-flex-core/src/main/java/com/agentsflex/core/document/splitter/SimpleTokenizeSplitter.java b/agents-flex-core/src/main/java/com/agentsflex/core/document/splitter/SimpleTokenizeSplitter.java
index 346675b..05e92e6 100644
--- a/agents-flex-core/src/main/java/com/agentsflex/core/document/splitter/SimpleTokenizeSplitter.java
+++ b/agents-flex-core/src/main/java/com/agentsflex/core/document/splitter/SimpleTokenizeSplitter.java
@@ -105,18 +105,36 @@ public class SimpleTokenizeSplitter implements DocumentSplitter {
         while (currentIndex < maxIndex) {
             int endIndex = Math.min(currentIndex + chunkSize, maxIndex);
             List<Integer> chunkTokens = tokens.subList(currentIndex, endIndex);
-            currentIndex = currentIndex + chunkSize - overlapSize;
 
             IntArrayList intArrayList = new IntArrayList();
             for (Integer chunkToken : chunkTokens) {
                 intArrayList.add(chunkToken);
             }
             String chunkText = encoding.decode(intArrayList).trim();
-
             if (chunkText.isEmpty()) {
                 continue;
             }
 
+            //UTF-8 'Unicode replacement character' which in your case is 0xFFFD (65533 in Hex).
+            //fix 修复中文乱码的问题
+            boolean firstIsReplacement = chunkText.charAt(0) == 65533;
+            boolean lastIsReplacement = chunkText.charAt(chunkText.length() - 1) == 65533;
+
+            if (firstIsReplacement || lastIsReplacement) {
+                if (firstIsReplacement) currentIndex -= 1;
+                if (lastIsReplacement) endIndex += 1;
+
+                chunkTokens = tokens.subList(currentIndex, endIndex);
+                intArrayList = new IntArrayList();
+                for (Integer chunkToken : chunkTokens) {
+                    intArrayList.add(chunkToken);
+                }
+
+                chunkText = encoding.decode(intArrayList).trim();
+            }
+
+            currentIndex = currentIndex + chunkSize - overlapSize;
+
             Document newDocument = new Document();
             newDocument.addMetadata(document.getMetadataMap());
             newDocument.setContent(chunkText);
diff --git a/agents-flex-core/src/test/java/com/agentsflex/core/test/splitter/SimpleTokenizeSplitterTest.java b/agents-flex-core/src/test/java/com/agentsflex/core/test/splitter/SimpleTokenizeSplitterTest.java
index 9bde851..3d6c371 100644
--- a/agents-flex-core/src/test/java/com/agentsflex/core/test/splitter/SimpleTokenizeSplitterTest.java
+++ b/agents-flex-core/src/test/java/com/agentsflex/core/test/splitter/SimpleTokenizeSplitterTest.java
@@ -40,7 +40,7 @@ public class SimpleTokenizeSplitterTest {
 
     @Test
     public void test02() {
-        SimpleTokenizeSplitter splitter = new SimpleTokenizeSplitter(20, 3);
+        SimpleTokenizeSplitter splitter = new SimpleTokenizeSplitter(20, 4);
         List<Document> chunks = splitter.split(Document.of(text));
 
         for (Document chunk : chunks) {