diff --git a/rules-tests/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector/Fixture/also_update_generic_collection_docblock.php.inc b/rules-tests/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector/Fixture/also_update_generic_collection_docblock.php.inc
new file mode 100644
index 00000000000..bbdf8a63297
--- /dev/null
+++ b/rules-tests/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector/Fixture/also_update_generic_collection_docblock.php.inc
@@ -0,0 +1,41 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\NarrowObjectReturnTypeRector\Fixture;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
+use stdClass;
+
+final class AlsoUpdateGenericCollectionDocblock
+{
+    /**
+     * @return Collection<int, stdClass>
+     */
+    protected function build(): Collection
+    {
+        return new ArrayCollection([new stdClass()]);
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\NarrowObjectReturnTypeRector\Fixture;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use Doctrine\Common\Collections\Collection;
+use stdClass;
+
+final class AlsoUpdateGenericCollectionDocblock
+{
+    /**
+     * @return \Doctrine\Common\Collections\ArrayCollection<int, stdClass>
+     */
+    protected function build(): \Doctrine\Common\Collections\ArrayCollection
+    {
+        return new ArrayCollection([new stdClass()]);
+    }
+}
+
+?>
diff --git a/rules/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector.php b/rules/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector.php
index 08da3729d4c..b4d4ef931c6 100644
--- a/rules/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector.php
+++ b/rules/TypeDeclaration/Rector/ClassMethod/NarrowObjectReturnTypeRector.php
@@ -8,8 +8,14 @@
 use PhpParser\Node\Identifier;
 use PhpParser\Node\Name\FullyQualified;
 use PhpParser\Node\Stmt\ClassMethod;
+use PHPStan\PhpDocParser\Ast\PhpDoc\ReturnTagValueNode;
+use PHPStan\PhpDocParser\Ast\Type\GenericTypeNode;
 use PHPStan\Reflection\ClassReflection;
 use PHPStan\Type\ObjectType;
+use Rector\BetterPhpDocParser\PhpDocInfo\PhpDocInfo;
+use Rector\BetterPhpDocParser\PhpDocInfo\PhpDocInfoFactory;
+use Rector\BetterPhpDocParser\ValueObject\Type\FullyQualifiedIdentifierTypeNode;
+use Rector\Comments\NodeDocBlock\DocBlockUpdater;
 use Rector\PhpParser\AstResolver;
 use Rector\PhpParser\Node\BetterNodeFinder;
 use Rector\Rector\AbstractRector;
@@ -28,6 +34,8 @@ public function __construct(
         private readonly BetterNodeFinder $betterNodeFinder,
         private readonly ReflectionResolver $reflectionResolver,
         private readonly AstResolver $astResolver,
+        private readonly PhpDocInfoFactory $phpDocInfoFactory,
+        private readonly DocBlockUpdater $docBlockUpdater
     ) {
     }
 
@@ -140,9 +148,31 @@ public function refactor(Node $node): ?Node
 
         $node->returnType = new FullyQualified($actualReturnClass);
 
+        $this->updateDocblock($node, $actualReturnClass);
+
         return $node;
     }
 
+    private function updateDocblock(ClassMethod $classMethod, string $actualReturnClass): void
+    {
+        $phpDocInfo = $this->phpDocInfoFactory->createFromNode($classMethod);
+        if (! $phpDocInfo instanceof PhpDocInfo) {
+            return;
+        }
+
+        $returnTagValueNode = $phpDocInfo->getReturnTagValue();
+        if (! $returnTagValueNode instanceof ReturnTagValueNode) {
+            return;
+        }
+
+        if (! $returnTagValueNode->type instanceof GenericTypeNode) {
+            return;
+        }
+
+        $returnTagValueNode->type->type = new FullyQualifiedIdentifierTypeNode($actualReturnClass);
+        $this->docBlockUpdater->updateRefactoredNodeWithPhpDocInfo($classMethod);
+    }
+
     private function isDeclaredTypeFinal(string $declaredType): bool
     {
         if ($declaredType === 'object') {