diff --git a/modules/openapi-generator/src/main/resources/avro-schema/pojo.mustache b/modules/openapi-generator/src/main/resources/avro-schema/pojo.mustache
index 0472804f293..e6967d322a3 100644
--- a/modules/openapi-generator/src/main/resources/avro-schema/pojo.mustache
+++ b/modules/openapi-generator/src/main/resources/avro-schema/pojo.mustache
@@ -3,7 +3,8 @@
     {
       "name": "{{baseName}}",
       "type": {{^required}}["null", {{/required}}{{>typeProperty}}{{^required}}]{{/required}},
-      "doc": "{{{description}}}"
+      "doc": "{{{description}}}"{{^required}},
+      "default": null{{/required}}
     }{{^-last}},{{/-last}}
   {{/vars}}
-  ]
\ No newline at end of file
+  ]
diff --git a/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/FILES b/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/FILES
new file mode 100644
index 00000000000..894d1ff1db0
--- /dev/null
+++ b/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/FILES
@@ -0,0 +1,8 @@
+ApiResponse.avsc
+Category.avsc
+InlineObject.avsc
+InlineObject1.avsc
+Order.avsc
+Pet.avsc
+Tag.avsc
+User.avsc
diff --git a/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/VERSION b/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/VERSION
index c3a2c7076fa..d99e7162d01 100644
--- a/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/VERSION
+++ b/samples/openapi3/schema/petstore/avro-schema/.openapi-generator/VERSION
@@ -1 +1 @@
-4.2.0-SNAPSHOT
\ No newline at end of file
+5.0.0-SNAPSHOT
\ No newline at end of file
diff --git a/samples/openapi3/schema/petstore/avro-schema/ApiResponse.avsc b/samples/openapi3/schema/petstore/avro-schema/ApiResponse.avsc
index d3ce5cc6aea..f105b1688d3 100644
--- a/samples/openapi3/schema/petstore/avro-schema/ApiResponse.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/ApiResponse.avsc
@@ -7,17 +7,21 @@
     {
       "name": "code",
       "type": ["null", "int"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "type",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "message",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/Category.avsc b/samples/openapi3/schema/petstore/avro-schema/Category.avsc
index 527f2d389cd..1ff49df61c0 100644
--- a/samples/openapi3/schema/petstore/avro-schema/Category.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/Category.avsc
@@ -7,12 +7,15 @@
     {
       "name": "id",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "name",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/InlineObject.avsc b/samples/openapi3/schema/petstore/avro-schema/InlineObject.avsc
index 70af82014c9..57b4895da79 100644
--- a/samples/openapi3/schema/petstore/avro-schema/InlineObject.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/InlineObject.avsc
@@ -7,12 +7,15 @@
     {
       "name": "name",
       "type": ["null", "string"],
-      "doc": "Updated name of the pet"
+      "doc": "Updated name of the pet",
+      "default": null
     },
     {
       "name": "status",
       "type": ["null", "string"],
-      "doc": "Updated status of the pet"
+      "doc": "Updated status of the pet",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/InlineObject1.avsc b/samples/openapi3/schema/petstore/avro-schema/InlineObject1.avsc
index 322dae3751e..6ef90935203 100644
--- a/samples/openapi3/schema/petstore/avro-schema/InlineObject1.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/InlineObject1.avsc
@@ -7,12 +7,15 @@
     {
       "name": "additionalMetadata",
       "type": ["null", "string"],
-      "doc": "Additional data to pass to server"
+      "doc": "Additional data to pass to server",
+      "default": null
     },
     {
       "name": "file",
       "type": ["null", "model.File"],
-      "doc": "file to upload"
+      "doc": "file to upload",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/Order.avsc b/samples/openapi3/schema/petstore/avro-schema/Order.avsc
index 945f42d579e..c1d5e6c0e6e 100644
--- a/samples/openapi3/schema/petstore/avro-schema/Order.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/Order.avsc
@@ -7,22 +7,26 @@
     {
       "name": "id",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "petId",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "quantity",
       "type": ["null", "int"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "shipDate",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "status",
@@ -35,12 +39,15 @@
           "delivered"
         ]
       }],
-      "doc": "Order Status"
+      "doc": "Order Status",
+      "default": null
     },
     {
       "name": "complete",
       "type": ["null", "boolean"],
-      "doc": ""
+      "doc": "",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/Pet.avsc b/samples/openapi3/schema/petstore/avro-schema/Pet.avsc
index 46ccf5f3d66..b2925056c20 100644
--- a/samples/openapi3/schema/petstore/avro-schema/Pet.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/Pet.avsc
@@ -7,12 +7,14 @@
     {
       "name": "id",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "category",
       "type": ["null", "model.Category"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "name",
@@ -33,7 +35,8 @@
         "type": "array",
         "items": "model.Tag"
       }],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "status",
@@ -46,7 +49,9 @@
           "sold"
         ]
       }],
-      "doc": "pet status in the store"
+      "doc": "pet status in the store",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/Tag.avsc b/samples/openapi3/schema/petstore/avro-schema/Tag.avsc
index ec31d8fb17a..ad5b34e5d4a 100644
--- a/samples/openapi3/schema/petstore/avro-schema/Tag.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/Tag.avsc
@@ -7,12 +7,15 @@
     {
       "name": "id",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "name",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     }
   ]
+
 }
diff --git a/samples/openapi3/schema/petstore/avro-schema/User.avsc b/samples/openapi3/schema/petstore/avro-schema/User.avsc
index 2654a817946..53f1f9d36e5 100644
--- a/samples/openapi3/schema/petstore/avro-schema/User.avsc
+++ b/samples/openapi3/schema/petstore/avro-schema/User.avsc
@@ -7,42 +7,51 @@
     {
       "name": "id",
       "type": ["null", "long"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "username",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "firstName",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "lastName",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "email",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "password",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "phone",
       "type": ["null", "string"],
-      "doc": ""
+      "doc": "",
+      "default": null
     },
     {
       "name": "userStatus",
       "type": ["null", "int"],
-      "doc": "User Status"
+      "doc": "User Status",
+      "default": null
     }
   ]
+
 }