diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java
index 75123e86a30..a979dff275f 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java
@@ -559,7 +559,9 @@ public class ModelUtils {
         }
 
         // additionalProperties explicitly set to false
-        if (schema.getAdditionalProperties() instanceof Boolean && Boolean.FALSE.equals(schema.getAdditionalProperties())) {
+        if ((schema.getAdditionalProperties() instanceof Boolean && Boolean.FALSE.equals(schema.getAdditionalProperties())) ||
+            (schema.getAdditionalProperties() instanceof Schema && Boolean.FALSE.equals(((Schema) schema.getAdditionalProperties()).getBooleanSchemaValue()))
+        ) {
             return false;
         }
 
@@ -808,7 +810,13 @@ public class ModelUtils {
                 (null != schema.getProperties() && !schema.getProperties().isEmpty()) &&
                 // no additionalProperties is set
                 (schema.getAdditionalProperties() == null ||
-                        (schema.getAdditionalProperties() instanceof Boolean && !(Boolean) schema.getAdditionalProperties()));
+                // additionalProperties is boolean and set to false
+                (schema.getAdditionalProperties() instanceof Boolean && !(Boolean) schema.getAdditionalProperties()) ||
+                // additionalProperties is a schema with its boolean value set to false
+                (schema.getAdditionalProperties() instanceof Schema &&
+                        ((Schema) schema.getAdditionalProperties()).getBooleanSchemaValue() != null &&
+                              !((Schema) schema.getAdditionalProperties()).getBooleanSchemaValue())
+                );
     }
 
     public static boolean hasValidation(Schema sc) {
@@ -2422,7 +2430,7 @@ public class ModelUtils {
      * For example, a schema that only has a `description` without any `properties` or `$ref` defined.
      *
      * @param schema the schema
-     * @return       if the schema is only metadata and not an actual type
+     * @return if the schema is only metadata and not an actual type
      */
     public static boolean isMetadataOnlySchema(Schema schema) {
         return !(schema.get$ref() != null ||
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/utils/ModelUtilsTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/utils/ModelUtilsTest.java
index 621e80de710..44e0e008368 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/utils/ModelUtilsTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/utils/ModelUtilsTest.java
@@ -353,6 +353,9 @@ public class ModelUtilsTest {
         Assert.assertNull(anyof1Property.getType());
         Assert.assertTrue(ModelUtils.hasAnyOf(anyof1Property));
         Assert.assertTrue(ModelUtils.isAnyOf(anyof1Property));
+
+        Schema objectSchema = ModelUtils.getSchema(openAPI, "ObjectSchema");
+        Assert.assertFalse(ModelUtils.isMapSchema(objectSchema));
     }
 
     // 3.1 spec tests
@@ -392,7 +395,7 @@ public class ModelUtilsTest {
         Assert.assertTrue(ModelUtils.isAnyOf(anyof2));
 
         Schema objectSchema = ModelUtils.getSchema(openAPI, "ObjectSchema");
-        Assert.assertTrue(ModelUtils.isMapSchema(objectSchema));
+        Assert.assertFalse(ModelUtils.isMapSchema(objectSchema));
 
         Schema complexComposedSchema = ModelUtils.getSchema(openAPI, "ComplexComposedSchema");
         Assert.assertTrue(ModelUtils.isComplexComposedSchema(complexComposedSchema));
@@ -641,4 +644,35 @@ public class ModelUtilsTest {
         assertFalse(ModelUtils.isUnsupportedSchema(openAPI, (Schema) property2.getProperties().get("condition")));
         assertFalse(ModelUtils.isUnsupportedSchema(openAPI, (Schema) property2.getProperties().get("purpose")));
     }
+
+    @Test
+    public void testModelWithPropertiesOnly() {
+        // Schema with no properties
+        Schema testSchema = new ObjectSchema().properties(null);
+        assertFalse(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // Schema with properties
+        testSchema.setProperties(Map.of("foo", new Schema()));
+        assertTrue(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // Explicitly no additional properties
+        testSchema.setAdditionalProperties(false);
+        assertTrue(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // With additional properties
+        testSchema.setAdditionalProperties(true);
+        assertFalse(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // Additional properties is a schema set to false
+        testSchema.setAdditionalProperties(new Schema().booleanSchemaValue(false));
+        assertTrue(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // Additional properties is a schema set to true
+        testSchema.setAdditionalProperties(new Schema().booleanSchemaValue(true));
+        assertFalse(ModelUtils.isModelWithPropertiesOnly(testSchema));
+
+        // Additional properties is a custom schema
+        testSchema.setAdditionalProperties(new Schema().type("string"));
+        assertFalse(ModelUtils.isModelWithPropertiesOnly(testSchema));
+    }
 }
diff --git a/modules/openapi-generator/src/test/resources/3_0/schema.yaml b/modules/openapi-generator/src/test/resources/3_0/schema.yaml
index 2a6acce5c57..147e12d9c95 100644
--- a/modules/openapi-generator/src/test/resources/3_0/schema.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/schema.yaml
@@ -65,6 +65,14 @@ components:
           oneOf:
             - type: string
             - type: integer
+    ObjectSchema:
+      type: object
+      additionalProperties: false
+      properties:
+        name:
+          type: string
+        address:
+          type: string
     anyof1:
       anyOf:
         - type: string