diff --git a/doc/grammars/phpdoc-param.peg b/doc/grammars/phpdoc-param.peg
index 5a5c1b3..16c206e 100644
--- a/doc/grammars/phpdoc-param.peg
+++ b/doc/grammars/phpdoc-param.peg
@@ -1,9 +1,12 @@
 PhpDocParam
-  = AnnotationName Type IsVariadic? ParameterName Description?
+  = AnnotationName Type IsReference? IsVariadic? ParameterName Description?
 
 AnnotationName
   = '@param'
 
+IsReference
+  = '&'
+
 IsVariaric
   = '...'
 
diff --git a/src/Ast/PhpDoc/ParamTagValueNode.php b/src/Ast/PhpDoc/ParamTagValueNode.php
index eb88cd9..874180e 100644
--- a/src/Ast/PhpDoc/ParamTagValueNode.php
+++ b/src/Ast/PhpDoc/ParamTagValueNode.php
@@ -13,6 +13,9 @@ class ParamTagValueNode implements PhpDocTagValueNode
 	/** @var TypeNode */
 	public $type;
 
+	/** @var bool */
+	public $isReference;
+
 	/** @var bool */
 	public $isVariadic;
 
@@ -22,9 +25,10 @@ class ParamTagValueNode implements PhpDocTagValueNode
 	/** @var string (may be empty) */
 	public $description;
 
-	public function __construct(TypeNode $type, bool $isVariadic, string $parameterName, string $description)
+	public function __construct(TypeNode $type, bool $isReference, bool $isVariadic, string $parameterName, string $description)
 	{
 		$this->type = $type;
+		$this->isReference = $isReference;
 		$this->isVariadic = $isVariadic;
 		$this->parameterName = $parameterName;
 		$this->description = $description;
@@ -33,8 +37,9 @@ class ParamTagValueNode implements PhpDocTagValueNode
 
 	public function __toString(): string
 	{
+		$reference = $this->isReference ? '&' : '';
 		$variadic = $this->isVariadic ? '...' : '';
-		return trim("{$this->type} {$variadic}{$this->parameterName} {$this->description}");
+		return trim("{$this->type} {$reference}{$variadic}{$this->parameterName} {$this->description}");
 	}
 
 }
diff --git a/src/Parser/PhpDocParser.php b/src/Parser/PhpDocParser.php
index 704c69a..4231bcb 100644
--- a/src/Parser/PhpDocParser.php
+++ b/src/Parser/PhpDocParser.php
@@ -220,10 +220,11 @@ class PhpDocParser
 	private function parseParamTagValue(TokenIterator $tokens): Ast\PhpDoc\ParamTagValueNode
 	{
 		$type = $this->typeParser->parse($tokens);
+		$isReference = $tokens->tryConsumeTokenType(Lexer::TOKEN_REFERENCE);
 		$isVariadic = $tokens->tryConsumeTokenType(Lexer::TOKEN_VARIADIC);
 		$parameterName = $this->parseRequiredVariableName($tokens);
 		$description = $this->parseOptionalDescription($tokens);
-		return new Ast\PhpDoc\ParamTagValueNode($type, $isVariadic, $parameterName, $description);
+		return new Ast\PhpDoc\ParamTagValueNode($type, $isReference, $isVariadic, $parameterName, $description);
 	}
 
 
diff --git a/tests/PHPStan/Parser/PhpDocParserTest.php b/tests/PHPStan/Parser/PhpDocParserTest.php
index c65b032..a632e0e 100644
--- a/tests/PHPStan/Parser/PhpDocParserTest.php
+++ b/tests/PHPStan/Parser/PhpDocParserTest.php
@@ -99,6 +99,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 					new ParamTagValueNode(
 						new IdentifierTypeNode('Foo'),
 						false,
+						false,
 						'$foo',
 						''
 					)
@@ -115,6 +116,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 					new ParamTagValueNode(
 						new IdentifierTypeNode('Foo'),
 						false,
+						false,
 						'$foo',
 						'optional description'
 					)
@@ -130,6 +132,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 					'@param',
 					new ParamTagValueNode(
 						new IdentifierTypeNode('Foo'),
+						false,
 						true,
 						'$foo',
 						''
@@ -146,6 +149,75 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 					'@param',
 					new ParamTagValueNode(
 						new IdentifierTypeNode('Foo'),
+						false,
+						true,
+						'$foo',
+						'optional description'
+					)
+				),
+			]),
+		];
+
+		yield [
+			'OK reference without description',
+			'/** @param Foo &$foo */',
+			new PhpDocNode([
+				new PhpDocTagNode(
+					'@param',
+					new ParamTagValueNode(
+						new IdentifierTypeNode('Foo'),
+						true,
+						false,
+						'$foo',
+						''
+					)
+				),
+			]),
+		];
+
+		yield [
+			'OK reference with description',
+			'/** @param Foo &$foo optional description */',
+			new PhpDocNode([
+				new PhpDocTagNode(
+					'@param',
+					new ParamTagValueNode(
+						new IdentifierTypeNode('Foo'),
+						true,
+						false,
+						'$foo',
+						'optional description'
+					)
+				),
+			]),
+		];
+
+		yield [
+			'OK reference variadic without description',
+			'/** @param Foo &...$foo */',
+			new PhpDocNode([
+				new PhpDocTagNode(
+					'@param',
+					new ParamTagValueNode(
+						new IdentifierTypeNode('Foo'),
+						true,
+						true,
+						'$foo',
+						''
+					)
+				),
+			]),
+		];
+
+		yield [
+			'OK reference variadic with description',
+			'/** @param Foo &...$foo optional description */',
+			new PhpDocNode([
+				new PhpDocTagNode(
+					'@param',
+					new ParamTagValueNode(
+						new IdentifierTypeNode('Foo'),
+						true,
 						true,
 						'$foo',
 						'optional description'
@@ -1827,6 +1899,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Foo'),
 							false,
+							false,
 							'$foo',
 							'1st multi world description'
 						)
@@ -1836,6 +1909,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Bar'),
 							false,
+							false,
 							'$bar',
 							'2nd multi world description'
 						)
@@ -1855,6 +1929,7 @@ class PhpDocParserTest extends \PHPUnit\Framework\TestCase
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Foo'),
 							false,
+							false,
 							'$foo',
 							'1st multi world description
 some text in the middle'
@@ -1865,6 +1940,7 @@ some text in the middle'
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Bar'),
 							false,
+							false,
 							'$bar',
 							'2nd multi world description'
 						)
@@ -1895,6 +1971,7 @@ some text in the middle'
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Foo'),
 							false,
+							false,
 							'$foo',
 							'1st multi world description with empty lines'
 						)
@@ -1909,6 +1986,7 @@ some text in the middle'
 						new ParamTagValueNode(
 							new IdentifierTypeNode('Bar'),
 							false,
+							false,
 							'$bar',
 							'2nd multi world description with empty lines'
 						)
@@ -1942,6 +2020,7 @@ some text in the middle'
 						new ParamTagValueNode(
 							new IdentifierTypeNode('int'),
 							false,
+							false,
 							'$foo',
 							'@param string $bar'
 						)
@@ -2857,6 +2936,7 @@ some text in the middle'
 					new ParamTagValueNode(
 						new IdentifierTypeNode('class-string'),
 						false,
+						false,
 						'$test',
 						''
 					)
@@ -2873,6 +2953,7 @@ some text in the middle'
 					new ParamTagValueNode(
 						new IdentifierTypeNode('class-string'),
 						false,
+						false,
 						'$test',
 						'some description'
 					)
@@ -3166,6 +3247,7 @@ time are not reliable as field settings might be missing.'),
 					new ParamTagValueNode(
 						new IdentifierTypeNode('\Drupal\Core\Field\FieldStorageDefinitionInterface'),
 						false,
+						false,
 						'$field_definition',
 						''
 					)
@@ -3243,6 +3325,7 @@ time are not reliable as field settings might be missing.'),
 					new ParamTagValueNode(
 						new IdentifierTypeNode('Request'),
 						false,
+						false,
 						'$request',
 						'- The request object'
 					)
@@ -3463,6 +3546,7 @@ Finder::findFiles('*.php')
 				new ParamTagValueNode(
 					new ConstTypeNode(new ConstFetchNode('DateTimeImmutable', 'ATOM')),
 					false,
+					false,
 					'$a',
 					''
 				),