diff --git a/README.md b/README.md
index df48b47..5c3aced 100644
--- a/README.md
+++ b/README.md
@@ -442,6 +442,7 @@ class Example
 
 ### uselessPrivatePropertyNullability:
 - Detects useless nullability of a private property by checking type of all assignments.
+- Works only with natively typehinted properties
 - Recommended to be used with `uselessPrivatePropertyNullability` and `forbidUselessNullableReturn` as removing useless default value may cause useless nullability to be detected
 ```php
 class Example
diff --git a/src/Rule/UselessPrivatePropertyNullabilityRule.php b/src/Rule/UselessPrivatePropertyNullabilityRule.php
index 1861ed3..d53e5b0 100644
--- a/src/Rule/UselessPrivatePropertyNullabilityRule.php
+++ b/src/Rule/UselessPrivatePropertyNullabilityRule.php
@@ -83,12 +83,13 @@ public function processNode(Node $node, Scope $scope): array
             $propertyName = $property->getName();
             $defaultValueNode = $property->getDefault();
             $propertyReflection = $classReflection->getProperty($propertyName, $scope);
+            $definitionHasTypehint = $property->getNativeType() !== null;
             $definitionIsNullable = TypeCombinator::containsNull($propertyReflection->getWritableType());
             $nullIsAssigned = $nullabilityNeeded[$propertyName] ?? false;
             $hasNullDefaultValue = $defaultValueNode instanceof ConstFetch && $scope->resolveName($defaultValueNode->name) === 'null';
             $isUninitialized = isset($uninitializedProperties[$propertyName]);
 
-            if ($definitionIsNullable && !$nullIsAssigned && !$hasNullDefaultValue && !$isUninitialized) {
+            if ($definitionHasTypehint && $definitionIsNullable && !$nullIsAssigned && !$hasNullDefaultValue && !$isUninitialized) {
                 $errors[] = RuleErrorBuilder::message("Property {$className}::{$propertyName} is defined as nullable, but null is never assigned")->line($property->getLine())->build();
             }
         }
diff --git a/tests/Rule/data/UselessPrivatePropertyNullabilityRule/code.php b/tests/Rule/data/UselessPrivatePropertyNullabilityRule/code.php
index a29ae6f..2fa5d91 100644
--- a/tests/Rule/data/UselessPrivatePropertyNullabilityRule/code.php
+++ b/tests/Rule/data/UselessPrivatePropertyNullabilityRule/code.php
@@ -20,6 +20,9 @@ class ExampleClass
 
     private ?int $isUninitialized;
 
+    /** @var null|int */
+    private $isUninitializedWithoutTypehint;
+
     public function __construct(
         int $isPublic,
         int $isProtected,