diff --git a/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_non_string_default.php.inc b/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_non_string_default.php.inc
new file mode 100644
index 00000000000..d9e67e69283
--- /dev/null
+++ b/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_non_string_default.php.inc
@@ -0,0 +1,11 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\AddParamStringTypeFromSprintfUseRector\Fixture;
+
+final class SkipNonStringDefault
+{
+    public function test($name = 100)
+    {
+        return sprintf('Hello %s', $name);
+    }
+}
diff --git a/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php b/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
index 3454b42bcad..1b5bc35f8c8 100644
--- a/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
+++ b/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
@@ -5,7 +5,9 @@
 namespace Rector\TypeDeclaration\Rector\ClassMethod;
 
 use PhpParser\Node;
+use PhpParser\Node\Expr;
 use PhpParser\Node\Identifier;
+use PhpParser\Node\Scalar\String_;
 use PhpParser\Node\Stmt\ClassMethod;
 use PhpParser\Node\Stmt\Function_;
 use Rector\Rector\AbstractRector;
@@ -85,6 +87,11 @@ public function refactor(Node $node): ClassMethod|Function_|null
                 continue;
             }
 
+            // skip non string default value
+            if ($param->default instanceof Expr && ! $param->default instanceof String_) {
+                continue;
+            }
+
             /** @var string $variableName */
             $variableName = $this->getName($param->var);