diff --git a/core/src/main/java/com/alibaba/fastjson2/JSONPath.java b/core/src/main/java/com/alibaba/fastjson2/JSONPath.java
index b2c33f34b5..937b19eae4 100644
--- a/core/src/main/java/com/alibaba/fastjson2/JSONPath.java
+++ b/core/src/main/java/com/alibaba/fastjson2/JSONPath.java
@@ -2252,16 +2252,7 @@ public boolean contains(Object root) {
         public void set(Object rootObject, Object value) {
             if (rootObject instanceof Map) {
                 Map map = (Map) rootObject;
-                Object origin = map.put(name, value);
-                if (origin != null) {
-                    if (origin instanceof Collection) {
-                        ((Collection) origin).add(value);
-                        map.put(name, value);
-                    } else {
-                        JSONArray array = JSONArray.of(origin, value);
-                        map.put(name, array);
-                    }
-                }
+                map.put(name, value);
                 return;
             }
             ObjectReaderProvider provider = getReaderContext().getProvider();
diff --git a/core/src/test/java/com/alibaba/fastjson2/issues/Issue431.java b/core/src/test/java/com/alibaba/fastjson2/issues/Issue431.java
new file mode 100644
index 0000000000..bc541f8477
--- /dev/null
+++ b/core/src/test/java/com/alibaba/fastjson2/issues/Issue431.java
@@ -0,0 +1,38 @@
+package com.alibaba.fastjson2.issues;
+
+import com.alibaba.fastjson2.JSON;
+import com.alibaba.fastjson2.JSONObject;
+import com.alibaba.fastjson2.JSONPath;
+import com.alibaba.fastjson2.JSONReader;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class Issue431 {
+    @Test
+    public void test() {
+        String jsonStr = "{\"aaa\":\"a111\",\"bbb\":\"b11111\"}";
+        JSONObject jsonObject = JSON.parseObject(jsonStr);
+
+        String valueStr = "{\"ccc\":\"c111\",\"ddd\":\"d11111\"}";
+        JSONObject value = JSON.parseObject(valueStr);
+
+        JSONPath.set(jsonObject, "$.aaa", value);
+        assertEquals("{\"aaa\":{\"ccc\":\"c111\",\"ddd\":\"d11111\"},\"bbb\":\"b11111\"}", jsonObject.toString());
+    }
+
+    @Test
+    public void test1() {
+        JSONObject object = JSONObject.of("id", 123);
+        JSONPath path = JSONPath.of("$.id");
+
+        path.set(object, 101);
+        assertEquals(101, object.get("id"));
+
+        path.set(object, 102);
+        assertEquals(102, object.get("id"));
+
+        path.set(object, 103, JSONReader.Feature.DuplicateKeyValueAsArray);
+        assertEquals("[102,103]", object.get("id").toString());
+    }
+}