diff --git a/modules/openapi-generator/src/main/resources/Java/beanValidation.mustache b/modules/openapi-generator/src/main/resources/Java/beanValidation.mustache
index 1bc9afa8f68..47f7109e5bc 100644
--- a/modules/openapi-generator/src/main/resources/Java/beanValidation.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/beanValidation.mustache
@@ -1,5 +1,7 @@
 {{#required}}
+{{^isReadOnly}}
   @NotNull
+{{/isReadOnly}}
 {{/required}}
 {{#isContainer}}
 {{^isPrimitiveType}}
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/microprofile/beanValidation.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/microprofile/beanValidation.mustache
index c8c6946fef6..f8724b24429 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/microprofile/beanValidation.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/microprofile/beanValidation.mustache
@@ -1,4 +1,6 @@
 {{#required}}
+{{^isReadOnly}}
   @NotNull
+{{/isReadOnly}}
 {{/required}}
 {{>beanValidationCore}}
\ No newline at end of file
diff --git a/modules/openapi-generator/src/main/resources/JavaSpring/beanValidation.mustache b/modules/openapi-generator/src/main/resources/JavaSpring/beanValidation.mustache
index 34c7581d5d4..e427a43a0ac 100644
--- a/modules/openapi-generator/src/main/resources/JavaSpring/beanValidation.mustache
+++ b/modules/openapi-generator/src/main/resources/JavaSpring/beanValidation.mustache
@@ -1 +1 @@
-{{#required}}@NotNull {{/required}}{{#isContainer}}{{^isPrimitiveType}}{{^isEnum}}@Valid {{/isEnum}}{{/isPrimitiveType}}{{/isContainer}}{{^isContainer}}{{^isPrimitiveType}}@Valid {{/isPrimitiveType}}{{/isContainer}}{{>beanValidationCore}}
\ No newline at end of file
+{{#required}}{{^isReadOnly}}@NotNull {{/isReadOnly}}{{/required}}{{#isContainer}}{{^isPrimitiveType}}{{^isEnum}}@Valid {{/isEnum}}{{/isPrimitiveType}}{{/isContainer}}{{^isContainer}}{{^isPrimitiveType}}@Valid {{/isPrimitiveType}}{{/isContainer}}{{>beanValidationCore}}
\ No newline at end of file
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java
index 2c62cecc8c3..f467ee4af5e 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/spring/SpringCodegenTest.java
@@ -793,11 +793,73 @@ public class SpringCodegenTest {
                 assertEquals(desFile, DESTINATIONFILE);
             }
         }
-        if(!flag){
+        if (!flag) {
             fail("OpenAPIDocumentationConfig.java not generated");
         }
     }
 
+    @Test
+    public void shouldAddNotNullOnRequiredAttributes() throws IOException {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/spring/issue_5026-b.yaml");
+        final SpringCodegen codegen = new SpringCodegen();
+        codegen.setOpenAPI(openAPI);
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        ClientOptInput input = new ClientOptInput();
+        input.openAPI(openAPI);
+        input.config(codegen);
+
+        DefaultGenerator generator = new DefaultGenerator();
+
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODELS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_TESTS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_DOCS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.APIS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.SUPPORTING_FILES, "false");
+
+        generator.opts(input).generate();
+
+        assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java"), "status");
+        assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java"), "@NotNull");
+        Files.readAllLines(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java")).forEach(System.out::println);
+
+    }
+
+    @Test
+    public void shouldNotAddNotNullOnReadOnlyAttributes() throws IOException {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        String outputPath = output.getAbsolutePath().replace('\\', '/');
+
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/spring/issue_5026.yaml");
+        final SpringCodegen codegen = new SpringCodegen();
+        codegen.setOpenAPI(openAPI);
+        codegen.setOutputDir(output.getAbsolutePath());
+
+        ClientOptInput input = new ClientOptInput();
+        input.openAPI(openAPI);
+        input.config(codegen);
+
+        DefaultGenerator generator = new DefaultGenerator();
+
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODELS, "true");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_TESTS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.MODEL_DOCS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.APIS, "false");
+        generator.setGeneratorPropertyDefault(CodegenConstants.SUPPORTING_FILES, "false");
+
+        generator.opts(input).generate();
+
+        assertFileContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java"), "status");
+        assertFileNotContains(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java"), "@NotNull");
+        Files.readAllLines(Paths.get(outputPath + "/src/main/java/org/openapitools/model/Dummy.java")).forEach(System.out::println);
+
+    }
+
     @Test
     public void testTypeMappings() {
         final SpringCodegen codegen = new SpringCodegen();
diff --git a/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026-b.yaml b/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026-b.yaml
new file mode 100644
index 00000000000..1255e667cc2
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026-b.yaml
@@ -0,0 +1,34 @@
+openapi: 3.0.0
+info:
+  version: "1.0.0"
+  title: reactive-spring-boot-request-body-issue
+tags:
+  - name: ReactiveSpringBootRequestBodyIssue
+paths:
+  /some/dummy/endpoint:
+    post:
+      tags:
+        - ReactiveSpringBootRequestBodyIssue
+      requestBody:
+        description: request
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Dummy'
+        required: true
+      responses:
+        200:
+          description: Successfully created reverse listings for retail
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Dummy'
+components:
+  schemas:
+    Dummy:
+      required:
+        - status
+      type: object
+      properties:
+        status:
+          type: string
diff --git a/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026.yaml b/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026.yaml
new file mode 100644
index 00000000000..2031488ea7a
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/spring/issue_5026.yaml
@@ -0,0 +1,35 @@
+openapi: 3.0.0
+info:
+  version: "1.0.0"
+  title: reactive-spring-boot-request-body-issue
+tags:
+  - name: ReactiveSpringBootRequestBodyIssue
+paths:
+  /some/dummy/endpoint:
+    post:
+      tags:
+        - ReactiveSpringBootRequestBodyIssue
+      requestBody:
+        description: request
+        content:
+          application/json:
+            schema:
+              $ref: '#/components/schemas/Dummy'
+        required: true
+      responses:
+        200:
+          description: Successfully created reverse listings for retail
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Dummy'
+components:
+  schemas:
+    Dummy:
+      required:
+        - status
+      type: object
+      properties:
+        status:
+          type: string
+          readOnly: true