diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/CodegenModel.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/CodegenModel.java
index 62c46dd612f3..2a25b93d7c9c 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/CodegenModel.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/CodegenModel.java
@@ -58,7 +58,7 @@ public class CodegenModel {
     public Set<String> allMandatory;
 
     public Set<String> imports = new TreeSet<String>();
-    public boolean hasVars, emptyVars, hasMoreModels, hasEnums, isEnum, hasRequired, hasOptional, isArrayModel, hasChildren, isCollectionModel;
+    public boolean hasVars, emptyVars, hasMoreModels, hasEnums, isEnum, hasRequired, hasOptional, isArrayModel, hasChildren, isMapModel;
     public boolean hasOnlyReadOnly = true; // true if all properties are read-only
     public ExternalDocumentation externalDocumentation;
 
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
index 1c431a6c8f1f..9eb0a6fc3d90 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java
@@ -1412,7 +1412,6 @@ public class DefaultCodegen implements CodegenConfig {
 
         if (ModelUtils.isArraySchema(schema)) {
             m.isArrayModel = true;
-            m.isCollectionModel = true;
             m.arrayModelType = fromProperty(name, schema).complexType;
             addParentContainer(m, name, schema);
         } else if (schema instanceof ComposedSchema) {
@@ -1522,7 +1521,7 @@ public class DefaultCodegen implements CodegenConfig {
             }
             if (ModelUtils.isMapSchema(schema)) {
                 addAdditionPropertiesToCodeGenModel(m, schema);
-                m.isCollectionModel = true;
+                m.isMapModel = true;
             }
             addVars(m, schema.getProperties(), schema.getRequired());
         }
diff --git a/modules/openapi-generator/src/main/resources/aspnetcore/model.mustache b/modules/openapi-generator/src/main/resources/aspnetcore/model.mustache
index 3307a41dd7df..7b06958ef679 100644
--- a/modules/openapi-generator/src/main/resources/aspnetcore/model.mustache
+++ b/modules/openapi-generator/src/main/resources/aspnetcore/model.mustache
@@ -56,7 +56,7 @@ namespace {{packageName}}.Models
         /// Returns the JSON string presentation of the object
         /// </summary>
         /// <returns>JSON string presentation of the object</returns>
-        public {{#parent}}{{^isCollectionModel}}new {{/isCollectionModel}}{{/parent}}string ToJson()
+        public {{#parent}}{{^isMapModel}}{{^isArrayModel}}new {{/isArrayModel}}{{/isMapModel}}{{/parent}}string ToJson()
         {
             return JsonConvert.SerializeObject(this, Formatting.Indented);
         }