diff --git a/src/Type/Php/GetDefinedVarsFunctionReturnTypeExtension.php b/src/Type/Php/GetDefinedVarsFunctionReturnTypeExtension.php
index e401fd3f31..16c99f1381 100644
--- a/src/Type/Php/GetDefinedVarsFunctionReturnTypeExtension.php
+++ b/src/Type/Php/GetDefinedVarsFunctionReturnTypeExtension.php
@@ -35,6 +35,10 @@ public function getTypeFromFunctionCall(FunctionReflection $functionReflection,
 		$typeBuilder = ConstantArrayTypeBuilder::createEmpty();
 
 		foreach ($scope->getDefinedVariables() as $variable) {
+			if ($variable === 'this') {
+				continue;
+			}
+
 			$typeBuilder->setOffsetValueType(new ConstantStringType($variable), $scope->getVariableType($variable), false);
 		}
 
diff --git a/tests/PHPStan/Analyser/nsrt/get-defined-vars.php b/tests/PHPStan/Analyser/nsrt/get-defined-vars.php
index 345d54dbd3..f61a316d88 100644
--- a/tests/PHPStan/Analyser/nsrt/get-defined-vars.php
+++ b/tests/PHPStan/Analyser/nsrt/get-defined-vars.php
@@ -44,3 +44,13 @@ function doRandom(int $param) {
 	}
 	assertType('array{param: int, local: \'foo\', random2?: \'baz\', random1?: \'bar\'}', get_defined_vars());
 }
+
+class A
+{
+	public function test(): void
+	{
+		$local = 'foo';
+
+		assertType('array{local: \'foo\'}', get_defined_vars());
+	}
+}
diff --git a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
index 0dbebf0da3..a4d8f415e7 100644
--- a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
+++ b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
@@ -3666,6 +3666,16 @@ public function testBug3396(): void
 		$this->analyse([__DIR__ . '/data/bug-3396.php'], []);
 	}
 
+	#[RequiresPhp('>= 8.0')]
+	public function testBug13881(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->checkExplicitMixed = true;
+		$this->analyse([__DIR__ . '/data/bug-13881.php'], []);
+	}
+
 	public function testBug13511(): void
 	{
 		$this->checkThisOnly = false;
diff --git a/tests/PHPStan/Rules/Methods/data/bug-13881.php b/tests/PHPStan/Rules/Methods/data/bug-13881.php
new file mode 100644
index 0000000000..a618bd5b70
--- /dev/null
+++ b/tests/PHPStan/Rules/Methods/data/bug-13881.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace Bug13881;
+
+class A {
+
+	public function test(string $functionArg): void {
+		$localVariable = "test";
+
+		$map = [
+			"var" => "1",
+		];
+
+		$values = get_defined_vars();
+
+		unset($values["map"]);
+		unset($values["functionArg"]);
+		unset($values["localVariable"]);
+		//unset($values["this"]);
+
+		foreach ($map as $field => $val) {
+			$values[$field] = $val;
+		}
+
+		$this->varDump(...$values);
+	}
+
+	public function varDump(mixed $var): void {
+		var_dump($var);
+	}
+}
+
+$a = new A();
+$a->test("a");