diff --git a/api-test/backend/src/main/java/io/metersphere/api/dto/scenario/Body.java b/api-test/backend/src/main/java/io/metersphere/api/dto/scenario/Body.java
index 8b1c96413d..f37f53fc8e 100644
--- a/api-test/backend/src/main/java/io/metersphere/api/dto/scenario/Body.java
+++ b/api-test/backend/src/main/java/io/metersphere/api/dto/scenario/Body.java
@@ -4,9 +4,9 @@ import io.metersphere.api.exec.generator.JSONSchemaRunTest;
 import io.metersphere.commons.constants.StorageConstants;
 import io.metersphere.commons.utils.FileUtils;
 import io.metersphere.commons.utils.JSON;
+import io.metersphere.commons.utils.JSONUtil;
 import io.metersphere.jmeter.utils.ScriptEngineUtils;
 import io.metersphere.request.BodyFile;
-import io.metersphere.commons.utils.JSONUtil;
 import io.metersphere.utils.LoggerUtil;
 import lombok.Data;
 import org.apache.commons.collections4.CollectionUtils;
@@ -20,6 +20,7 @@ import org.json.JSONObject;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.stream.Collectors;
 
 @Data
@@ -38,6 +39,7 @@ public class Body {
     public final static String BINARY = "BINARY";
     public final static String JSON_STR = "JSON";
     public final static String XML = "XML";
+    public final static String JSON_SCHEMA = "JSON-SCHEMA";
 
     public boolean isValid() {
         if (this.isKV()) {
@@ -82,7 +84,7 @@ public class Body {
         } else {
             if (StringUtils.isNotEmpty(this.getRaw()) || this.getJsonSchema() != null) {
                 parseJonBodyMock();
-                KeyValue keyValue = new KeyValue(StringUtils.EMPTY, "JSON-SCHEMA", this.getRaw(), true, true);
+                KeyValue keyValue = new KeyValue(StringUtils.EMPTY, JSON_SCHEMA, this.getRaw(), true, true);
                 sampler.setPostBodyRaw(true);
                 keyValue.setEnable(true);
                 keyValue.setUrlEncode(false);
@@ -93,18 +95,18 @@ public class Body {
     }
 
     private void parseJonBodyMock() {
-        if (StringUtils.isNotBlank(this.type) && StringUtils.equals(this.type, "JSON")) {
+        if (StringUtils.isNotBlank(this.type) && StringUtils.equals(this.type, JSON_STR)) {
             if (StringUtils.isNotEmpty(this.format) && this.getJsonSchema() != null
-                    && "JSON-SCHEMA".equals(this.format)) {
+                    && JSON_SCHEMA.equals(this.format)) {
                 this.raw = StringEscapeUtils.unescapeJava(JSONSchemaRunTest.getJson(JSON.toJSONString(this.getJsonSchema())));
             } else {
                 try {
                     if (StringUtils.isNotEmpty(this.getRaw())) {
-                        JSONObject jsonObject = JSONUtil.parseObject(this.getRaw());
+                        Map<String, Object> map = JSON.parseObject(this.getRaw(), Map.class);
                         if (!this.getRaw().contains("$ref")) {
-                            jsonMockParse(jsonObject);
+                            jsonMockParse(map);
                         }
-                        this.raw = JSONUtil.parser(jsonObject.toString());
+                        this.raw = JSONUtil.parser(map.toString());
                     }
                 } catch (Exception e) {
                     LoggerUtil.error("json mock value is abnormal", e);
@@ -113,16 +115,16 @@ public class Body {
         }
     }
 
-    private void jsonMockParse(JSONObject jsonObject) {
-        for (String key : jsonObject.keySet()) {
-            Object value = jsonObject.get(key);
+    private void jsonMockParse(Map map) {
+        for (Object key : map.keySet()) {
+            Object value = map.get(key);
             if (value instanceof JSONObject) {
-                jsonMockParse((JSONObject) value);
+                jsonMockParse((Map) value);
             } else if (value instanceof String) {
                 if (StringUtils.isNotBlank((String) value)) {
                     value = ScriptEngineUtils.buildFunctionCallString((String) value);
                 }
-                jsonObject.put(key, value);
+                map.put(key, value);
             }
         }
     }
diff --git a/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaGenerator.java b/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaGenerator.java
index 80a9c14afa..d1feffe545 100644
--- a/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaGenerator.java
+++ b/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaGenerator.java
@@ -241,7 +241,7 @@ public class JSONSchemaGenerator {
                 concept.put(propertyName, obj);
                 analyzeObject(object, obj);
             } else if (StringUtils.equalsIgnoreCase(propertyObjType, "null")) {
-                concept.put(propertyName, StringUtils.EMPTY);
+                concept.put(propertyName, JSONObject.NULL);
             }
         }
     }
diff --git a/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaRunTest.java b/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaRunTest.java
index 519759f689..6770dfa4fc 100644
--- a/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaRunTest.java
+++ b/api-test/backend/src/main/java/io/metersphere/api/exec/generator/JSONSchemaRunTest.java
@@ -240,7 +240,7 @@ public class JSONSchemaRunTest {
             concept.put(propertyName, obj);
             analyzeObject(object, obj, map);
         } else if (StringUtils.equalsIgnoreCase(propertyObjType, "null")) {
-            concept.put(propertyName, StringUtils.EMPTY);
+            concept.put(propertyName, JSONObject.NULL);
         }
     }
 
diff --git a/api-test/backend/src/main/java/io/metersphere/commons/utils/JSONUtil.java b/api-test/backend/src/main/java/io/metersphere/commons/utils/JSONUtil.java
index b153e7d5f4..47b764e34f 100644
--- a/api-test/backend/src/main/java/io/metersphere/commons/utils/JSONUtil.java
+++ b/api-test/backend/src/main/java/io/metersphere/commons/utils/JSONUtil.java
@@ -243,7 +243,7 @@ public class JSONUtil {
 
     public static String parser(String content) {
         try {
-            Gson gson = new GsonBuilder().setPrettyPrinting().create();
+            Gson gson = new GsonBuilder().setPrettyPrinting().serializeNulls().create();
             return gson.toJson(JsonParser.parseString(content).getAsJsonObject());
         } catch (Exception e) {
             return content;
diff --git a/api-test/frontend/src/business/commons/json-schema/convert/convert.js b/api-test/frontend/src/business/commons/json-schema/convert/convert.js
index a35546c8cf..c68e277cee 100644
--- a/api-test/frontend/src/business/commons/json-schema/convert/convert.js
+++ b/api-test/frontend/src/business/commons/json-schema/convert/convert.js
@@ -230,8 +230,8 @@ class Convert {
     } else if (isString(value)) {
       objectTemplate.type = 'string';
     } else if (isNull(value)) {
-      objectTemplate.type = 'string';
-      objectTemplate.mock = { mock: '' };
+      objectTemplate.type = 'null';
+      objectTemplate['mock'] = undefined;
     } else if (isArray(value)) {
       objectTemplate.type = 'array';
       objectTemplate['mock'] = undefined;
diff --git a/api-test/frontend/src/business/commons/json-schema/schema/editor/main.vue b/api-test/frontend/src/business/commons/json-schema/schema/editor/main.vue
index 3c2e34f64c..3304fc2bb3 100644
--- a/api-test/frontend/src/business/commons/json-schema/schema/editor/main.vue
+++ b/api-test/frontend/src/business/commons/json-schema/schema/editor/main.vue
@@ -475,6 +475,10 @@ export default {
         if (this.isArray(this.pickValue)) {
           this.$set(this.pickValue, 'items', [{ type: 'string', mock: { mock: '' } }]);
         }
+        if (this.pickValue.type === 'null') {
+          this.$set(this.pickValue, 'mock', { mock: '' });
+          this.reloadItems();
+        }
       }
     },
     changeAllItemsType(changeType) {
diff --git a/api-test/frontend/src/business/commons/json-schema/schema/editor/type/type.js b/api-test/frontend/src/business/commons/json-schema/schema/editor/type/type.js
index f71c6a86ab..4530678a50 100644
--- a/api-test/frontend/src/business/commons/json-schema/schema/editor/type/type.js
+++ b/api-test/frontend/src/business/commons/json-schema/schema/editor/type/type.js
@@ -5,7 +5,7 @@ import _boolean from './boolean';
 import _integer from './integer';
 import _number from './number';
 
-const TYPE_NAME = ['string', 'number', 'integer', 'object', 'array', 'boolean'];
+const TYPE_NAME = ['string', 'number', 'integer', 'object', 'array', 'boolean', 'null'];
 
 const TYPE = {
   object: _object,
@@ -14,6 +14,7 @@ const TYPE = {
   boolean: _boolean,
   integer: _integer,
   number: _number,
+  null: { description: null },
 };
 export { TYPE, TYPE_NAME };