diff --git a/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Fixture/child_extends_parent_already_readonly.php.inc b/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Fixture/child_extends_parent_already_readonly.php.inc
new file mode 100644
index 00000000000..a5ee64c9da0
--- /dev/null
+++ b/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Fixture/child_extends_parent_already_readonly.php.inc
@@ -0,0 +1,29 @@
+<?php
+
+namespace Rector\Tests\Php82\Rector\Class_\ReadOnlyClassRector\Fixture;
+
+use Rector\Tests\Php82\Rector\Class_\ReadOnlyClassRector\Source\ParentAlreadyReadonly;
+
+/**
+ * Even class is not final, if extends class that already readonly, it must be readonly as well
+ */
+class ChildExtendsParentAlreadyReadonly extends ParentAlreadyReadonly
+{
+}
+
+?>
+-----
+<?php
+
+namespace Rector\Tests\Php82\Rector\Class_\ReadOnlyClassRector\Fixture;
+
+use Rector\Tests\Php82\Rector\Class_\ReadOnlyClassRector\Source\ParentAlreadyReadonly;
+
+/**
+ * Even class is not final, if extends class that already readonly, it must be readonly as well
+ */
+readonly class ChildExtendsParentAlreadyReadonly extends ParentAlreadyReadonly
+{
+}
+
+?>
diff --git a/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Source/ParentAlreadyReadonly.php b/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Source/ParentAlreadyReadonly.php
new file mode 100644
index 00000000000..f15b0c5b6c7
--- /dev/null
+++ b/rules-tests/Php82/Rector/Class_/ReadOnlyClassRector/Source/ParentAlreadyReadonly.php
@@ -0,0 +1,7 @@
+<?php
+
+namespace Rector\Tests\Php82\Rector\Class_\ReadOnlyClassRector\Source;
+
+readonly abstract class ParentAlreadyReadonly
+{
+}
diff --git a/rules/Php82/Rector/Class_/ReadOnlyClassRector.php b/rules/Php82/Rector/Class_/ReadOnlyClassRector.php
index 7cb799b85b4..0022af40672 100644
--- a/rules/Php82/Rector/Class_/ReadOnlyClassRector.php
+++ b/rules/Php82/Rector/Class_/ReadOnlyClassRector.php
@@ -104,22 +104,58 @@ public function provideMinPhpVersion(): int
         return PhpVersionFeature::READONLY_CLASS;
     }
 
+    /**
+     * @return ClassReflection[]
+     */
+    private function resolveParentClassReflections(Class_ $class): array
+    {
+        $classReflection = $this->reflectionResolver->resolveClassReflection($class);
+        if (! $classReflection instanceof ClassReflection) {
+            return [];
+        }
+
+        return $classReflection->getParents();
+    }
+
+    /**
+     * @param Property[] $properties
+     */
+    private function hasNonTypedProperty(array $properties): bool
+    {
+        foreach ($properties as $property) {
+            // properties of readonly class must always have type
+            if ($property->type === null) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     private function shouldSkip(Class_ $class): bool
     {
         if ($this->shouldSkipClass($class)) {
             return true;
         }
 
+        $parents = $this->resolveParentClassReflections($class);
+        if (! $class->isFinal()) {
+            return ! $this->isExtendsReadonlyClass($parents);
+        }
+
+        foreach ($parents as $parent) {
+            if (! $parent->isReadOnly()) {
+                return true;
+            }
+        }
+
         $properties = $class->getProperties();
         if ($this->hasWritableProperty($properties)) {
             return true;
         }
 
-        foreach ($properties as $property) {
-            // properties of readonly class must always have type
-            if ($property->type === null) {
-                return true;
-            }
+        if ($this->hasNonTypedProperty($properties)) {
+            return true;
         }
 
         $constructClassMethod = $class->getMethod(MethodName::CONSTRUCT);
@@ -137,6 +173,20 @@ private function shouldSkip(Class_ $class): bool
         return $this->shouldSkipParams($params);
     }
 
+    /**
+     * @param ClassReflection[] $parents
+     */
+    private function isExtendsReadonlyClass(array $parents): bool
+    {
+        foreach ($parents as $parent) {
+            if ($parent->isReadOnly()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     /**
      * @param Property[] $properties
      */
@@ -162,22 +212,6 @@ private function shouldSkipClass(Class_ $class): bool
             return true;
         }
 
-        if (! $class->isFinal()) {
-            return true;
-        }
-
-        $classReflection = $this->reflectionResolver->resolveClassReflection($class);
-        if (! $classReflection instanceof ClassReflection) {
-            return true;
-        }
-
-        $parents = $classReflection->getParents();
-        foreach ($parents as $parent) {
-            if (! $parent->isReadOnly()) {
-                return true;
-            }
-        }
-
         return $this->phpAttributeAnalyzer->hasPhpAttribute($class, AttributeName::ALLOW_DYNAMIC_PROPERTIES);
     }