diff --git a/rules-tests/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector/Fixture/both_annotation_and_attribute_exists.php.inc b/rules-tests/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector/Fixture/both_annotation_and_attribute_exists.php.inc
new file mode 100644
index 00000000..106c6ba5
--- /dev/null
+++ b/rules-tests/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector/Fixture/both_annotation_and_attribute_exists.php.inc
@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
+
+final class BothAnnotationAndAttributeExists extends TestCase
+{
+    /** @dataProvider provideData */
+    #[DataProvider('provideData')]
+    public function testExample(string $value): void
+    {
+        self::assertNotEmpty($value);
+    }
+
+    public static function provideData(): iterable
+    {
+        yield 'case 1' => ['foo'];
+        yield 'case 2' => ['bar'];
+    }
+}
+
+?>
+-----
+<?php
+
+declare(strict_types=1);
+
+use PHPUnit\Framework\Attributes\DataProvider;
+use PHPUnit\Framework\TestCase;
+
+final class BothAnnotationAndAttributeExists extends TestCase
+{
+    #[DataProvider('provideData')]
+    public function testExample(string $value): void
+    {
+        self::assertNotEmpty($value);
+    }
+
+    public static function provideData(): iterable
+    {
+        yield 'case 1' => ['foo'];
+        yield 'case 2' => ['bar'];
+    }
+}
+
+?>
\ No newline at end of file
diff --git a/rules/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector.php b/rules/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector.php
index e9bbc351..55470c4f 100644
--- a/rules/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector.php
+++ b/rules/AnnotationsToAttributes/Rector/ClassMethod/DataProviderAnnotationToAttributeRector.php
@@ -148,7 +148,11 @@ public function refactor(Node $node): ?Node
                 continue;
             }
 
-            $node->attrGroups[] = $this->createAttributeGroup($originalAttributeValueToken);
+            $attributeGroup = $this->createAttributeGroup($node, $originalAttributeValueToken);
+
+            if ($attributeGroup instanceof AttributeGroup) {
+                $node->attrGroups[] = $attributeGroup;
+            }
 
             // cleanup
             $this->phpDocTagRemover->removeTagValueFromNode($phpDocInfo, $desiredTagValueNode);
@@ -159,7 +163,7 @@ public function refactor(Node $node): ?Node
         return $node;
     }
 
-    private function createAttributeGroup(string $originalAttributeValue): AttributeGroup
+    private function createAttributeGroup(ClassMethod $classMethod, string $originalAttributeValue): ?AttributeGroup
     {
         $methodName = trim($originalAttributeValue, '()');
 
@@ -173,12 +177,23 @@ private function createAttributeGroup(string $originalAttributeValue): Attribute
                 $className = '\\' . $className;
             }
 
-            return $this->phpAttributeGroupFactory->createFromClassWithItems(
+            $attributeGroup = $this->phpAttributeGroupFactory->createFromClassWithItems(
                 'PHPUnit\Framework\Attributes\DataProviderExternal',
                 [$className . '::class', $methodName]
             );
+        } else {
+            $attributeGroup = $this->phpAttributeGroupFactory->createFromClassWithItems(
+                self::DATA_PROVIDER_CLASS,
+                [$methodName]
+            );
+        }
+
+        foreach ($classMethod->attrGroups as $existingAttributeGroup) {
+            if ($this->nodeComparator->areNodesEqual($existingAttributeGroup, $attributeGroup)) {
+                return null;
+            }
         }
 
-        return $this->phpAttributeGroupFactory->createFromClassWithItems(self::DATA_PROVIDER_CLASS, [$methodName]);
+        return $attributeGroup;
     }
 }