diff --git a/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/generic.php.inc b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/generic.php.inc
new file mode 100644
index 00000000000..4172dfbc3ab
--- /dev/null
+++ b/rules-tests/Php80/Rector/Class_/ClassPropertyAssignToConstructorPromotionRector/Fixture/generic.php.inc
@@ -0,0 +1,41 @@
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+/**
+ * @template T
+ */
+final class Generic
+{
+	/**
+	 * @var T
+	 */
+	public mixed $value;
+
+	/**
+	 * @param T $value
+	 */
+	public function __construct(mixed $value)
+	{
+		$this->value = $value;
+	}
+}
+?>
+-----
+<?php
+
+namespace Rector\Tests\Php80\Rector\Class_\ClassPropertyAssignToConstructorPromotionRector\Fixture;
+
+/**
+ * @template T
+ */
+final class Generic
+{
+	/**
+	 * @param T $value
+	 */
+	public function __construct(public mixed $value)
+	{
+	}
+}
+?>
diff --git a/rules/Php80/NodeAnalyzer/PromotedPropertyCandidateResolver.php b/rules/Php80/NodeAnalyzer/PromotedPropertyCandidateResolver.php
index 654ca3e9eed..462f6551ed4 100644
--- a/rules/Php80/NodeAnalyzer/PromotedPropertyCandidateResolver.php
+++ b/rules/Php80/NodeAnalyzer/PromotedPropertyCandidateResolver.php
@@ -12,6 +12,7 @@
 use PhpParser\Node\Stmt\ClassMethod;
 use PhpParser\Node\Stmt\Expression;
 use PhpParser\Node\Stmt\Property;
+use PHPStan\Type\Generic\TemplateType;
 use PHPStan\Type\Type;
 use PHPStan\Type\UnionType;
 use Rector\Core\PhpParser\Comparing\NodeComparator;
@@ -186,12 +187,11 @@ private function hasConflictingParamType(Param $param, Type $propertyType): bool
 
         $isAllFullyQualifiedObjectType = true;
         if ($propertyType instanceof UnionType) {
-            foreach ($propertyType->getTypes() as $type) {
-                if (! $type instanceof FullyQualifiedObjectType) {
-                    $isAllFullyQualifiedObjectType = false;
-                    break;
-                }
+            if ($this->hasGenericTemplateType($propertyType)) {
+                return false;
             }
+
+            $isAllFullyQualifiedObjectType = ! $this->hasNonFullyQualifiedObjectType($propertyType);
         }
 
         // different types, not a good to fit
@@ -201,6 +201,28 @@ private function hasConflictingParamType(Param $param, Type $propertyType): bool
         );
     }
 
+    private function hasNonFullyQualifiedObjectType(UnionType $unionType): bool
+    {
+        foreach ($unionType->getTypes() as $type) {
+            if (! $type instanceof FullyQualifiedObjectType) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    private function hasGenericTemplateType(UnionType $unionType): bool
+    {
+        foreach ($unionType->getTypes() as $type) {
+            if ($type instanceof TemplateType) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     /**
      * @param int[] $firstParamAsVariable
      */
@@ -215,12 +237,12 @@ private function shouldSkipParam(
             return true;
         }
 
-        // @todo unknown type, not suitable?
-        $propertyType = $this->propertyTypeInferer->inferProperty($property);
-        if ($this->hasConflictingParamType($matchedParam, $propertyType)) {
+        if ($this->isParamUsedBeforeAssign($assignedVariable, $firstParamAsVariable)) {
             return true;
         }
 
-        return $this->isParamUsedBeforeAssign($assignedVariable, $firstParamAsVariable);
+        // @todo unknown type, not suitable?
+        $propertyType = $this->propertyTypeInferer->inferProperty($property);
+        return $this->hasConflictingParamType($matchedParam, $propertyType);
     }
 }