diff --git a/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_conditional_non_string.php.inc b/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_conditional_non_string.php.inc
new file mode 100644
index 00000000000..1b071549e43
--- /dev/null
+++ b/rules-tests/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector/Fixture/skip_conditional_non_string.php.inc
@@ -0,0 +1,20 @@
+<?php
+
+namespace Rector\Tests\TypeDeclaration\Rector\ClassMethod\AddParamStringTypeFromSprintfUseRector\Fixture;
+
+final class SkipConditionalNonString
+{
+    /**
+     * @param false|float|int|string $cell
+     *
+     * @return bool|float|int|string
+     */
+    function run($data)
+    {
+        if (is_string($data)) {
+            $data = sprintf('"%s"', $data);
+        }
+
+        return $data;
+    }
+}
diff --git a/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php b/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
index d51dec28693..38f59b982f0 100644
--- a/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
+++ b/rules/TypeDeclaration/Rector/ClassMethod/AddParamStringTypeFromSprintfUseRector.php
@@ -13,6 +13,7 @@
 use PhpParser\Node\Stmt\ClassMethod;
 use PhpParser\Node\Stmt\Function_;
 use Rector\Rector\AbstractRector;
+use Rector\TypeDeclaration\Guard\ParamTypeAddGuard;
 use Rector\TypeDeclaration\NodeAnalyzer\VariableInSprintfMaskMatcher;
 use Rector\VendorLocker\ParentClassMethodTypeOverrideGuard;
 use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
@@ -26,6 +27,7 @@ final class AddParamStringTypeFromSprintfUseRector extends AbstractRector
     public function __construct(
         private readonly VariableInSprintfMaskMatcher $variableInSprintfMaskMatcher,
         private readonly ParentClassMethodTypeOverrideGuard $parentClassMethodTypeOverrideGuard,
+        private readonly ParamTypeAddGuard $paramTypeAddGuard
     ) {
     }
 
@@ -94,8 +96,11 @@ public function refactor(Node $node): ClassMethod|Function_|Closure|ArrowFunctio
                 continue;
             }
 
-            $variableName = $this->getName($param);
+            if (! $this->paramTypeAddGuard->isLegal($param, $node)) {
+                continue;
+            }
 
+            $variableName = $this->getName($param);
             if (! $this->variableInSprintfMaskMatcher->matchMask($node, $variableName, '%s')) {
                 continue;
             }