diff --git a/CHANGELOG.md b/CHANGELOG.md
index b1b6248..da2fad7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,7 +4,7 @@
 
  * The base of deviation of local variable abuse has been changed from the average number of rows to the first number of rows.
  * AssignOp has been added to the assignment decision in addition to Assign.
-
+ * Add filename to report json.
 
 ## v0.0.2 (2025-03-19)
 
diff --git a/src/Analyze/AnalysisResult.php b/src/Analyze/AnalysisResult.php
index 2c9c169..7efa880 100644
--- a/src/Analyze/AnalysisResult.php
+++ b/src/Analyze/AnalysisResult.php
@@ -13,6 +13,7 @@ final class AnalysisResult
      * @param list<Scope> $scopes
      */
     public function __construct(
+        public readonly string $filename,
         public readonly array $scopes
     )
     {
@@ -27,6 +28,7 @@ public function __construct(
     public function format(): string
     {
         $output = [
+            'filename' => $this->filename,
             'maxVariableHardUsage' => $this->maxVariableHardUsage,
             'avarageVariableHardUsage' => $this->avarageVariableHardUsage,
         ];
diff --git a/src/Analyze/VariableAnalyzer.php b/src/Analyze/VariableAnalyzer.php
index 2ff387e..fbcd641 100644
--- a/src/Analyze/VariableAnalyzer.php
+++ b/src/Analyze/VariableAnalyzer.php
@@ -11,22 +11,19 @@ final class VariableAnalyzer
 {
     private const ASSIGNED_VARIABLE_COEFFICIENT = 2;
 
-    /**
-     * @var list<Func>
-     */
-    private array $functions;
-
     /**
      * @param list<Func> $functions
      */
-    public function __construct(array $functions)
+    public function __construct(
+        public readonly string $filename,
+        public readonly array $functions
+    )
     {
-        $this->functions = $functions;
     }
 
     public function analyze(): AnalysisResult
     {
-        return new AnalysisResult(array_map(fn($f) => $this->analyzeFunction($f), $this->functions));
+        return new AnalysisResult($this->filename, array_map(fn($f) => $this->analyzeFunction($f), $this->functions));
     }
 
     private function analyzeFunction(Func $function): Scope
diff --git a/src/Command.php b/src/Command.php
index 66c5119..82c0a4d 100644
--- a/src/Command.php
+++ b/src/Command.php
@@ -32,7 +32,7 @@ public function run(array $argv): void
             return;
         }
         $parseResult = $parser->parse($content);
-        $analyzer = new VariableAnalyzer($parseResult->functions);
+        $analyzer = new VariableAnalyzer($filePath, $parseResult->functions);
         $result = $analyzer->analyze();
         echo $result->format();
     }
diff --git a/test/VariableAnalizerTest.php b/test/VariableAnalizerTest.php
index 77ba6d2..56c9690 100644
--- a/test/VariableAnalizerTest.php
+++ b/test/VariableAnalizerTest.php
@@ -16,8 +16,9 @@ public function testAnalyzeFunctionSimple(): void
         $func->addVariable(new VarReference('a', 2));
         $func->addVariable(new VarReference('a', 3));
 
-        $sut = new VariableAnalyzer([$func]);
+        $sut = new VariableAnalyzer('target.php', [$func]);
         $result = $sut->analyze();
+        $this->assertSame('target.php', $result->filename);
         $scopes = $result->scopes;
 
         $this->assertCount(1, $scopes);
@@ -32,8 +33,9 @@ public function testAnalyzeFunctionLong(): void
         $func->addVariable(new VarReference('a', 2));
         $func->addVariable(new VarReference('a', 100));
 
-        $sut = new VariableAnalyzer([$func]);
+        $sut = new VariableAnalyzer('target.php', [$func]);
         $result = $sut->analyze();
+        $this->assertSame('target.php', $result->filename);
         $scopes = $result->scopes;
 
         $this->assertCount(1, $scopes);
@@ -48,8 +50,9 @@ public function testAnalyzeFunctionLongAssignedVariable(): void
         $func->addVariable(new VarReference('a', 2));
         $func->addVariable(new VarReference('a', 100));
 
-        $sut = new VariableAnalyzer([$func]);
+        $sut = new VariableAnalyzer('target.php', [$func]);
         $result = $sut->analyze();
+        $this->assertSame('target.php', $result->filename);
         $scopes = $result->scopes;
 
         $this->assertCount(1, $scopes);
@@ -64,8 +67,9 @@ public function testAnalyzeFunctionLongMultipleAssignedVariable(): void
         $func->addVariable(new VarReference('a', 2));
         $func->addVariable(new VarReference('a', 100, true));
 
-        $sut = new VariableAnalyzer([$func]);
+        $sut = new VariableAnalyzer('target.php', [$func]);
         $result = $sut->analyze();
+        $this->assertSame('target.php', $result->filename);
         $scopes = $result->scopes;
 
         $this->assertCount(1, $scopes);