diff --git a/NEWS b/NEWS
index 52aa8b3bcf0..989e53f2850 100644
--- a/NEWS
+++ b/NEWS
@@ -12,6 +12,8 @@ PHP                                                                        NEWS
     (nielsdos)
   . Fix DOMCharacterData::replaceWith() with itself. (nielsdos)
   . Fix empty argument cases for DOMParentNode methods. (nielsdos)
+  . Fixed bug GH-11791 (Wrong default value of DOMDocument::xmlStandalone).
+    (nielsdos)
 
 - FFI:
   . Fix leaking definitions when using FFI::cdef()->new(...). (ilutov)
diff --git a/ext/dom/document.c b/ext/dom/document.c
index 71e12b6e7a9..e0eeb80fcb7 100644
--- a/ext/dom/document.c
+++ b/ext/dom/document.c
@@ -187,7 +187,7 @@ int dom_document_standalone_read(dom_object *obj, zval *retval)
 		return FAILURE;
 	}
 
-	ZVAL_BOOL(retval, docp->standalone);
+	ZVAL_BOOL(retval, docp->standalone > 0);
 	return SUCCESS;
 }
 
diff --git a/ext/dom/tests/domobject_debug_handler.phpt b/ext/dom/tests/domobject_debug_handler.phpt
index 8dbaa61a165..51750710545 100644
--- a/ext/dom/tests/domobject_debug_handler.phpt
+++ b/ext/dom/tests/domobject_debug_handler.phpt
@@ -12,53 +12,89 @@ XML;
 $d = new domdocument;
 $d->dynamicProperty = new stdclass;
 $d->loadXML($xml);
-print_r($d);
+var_dump($d);
 ?>
---EXPECTF--
-DOMDocument Object
-(
-    [config] => 
-    [dynamicProperty] => stdClass Object
-        (
-        )
-
-    [doctype] => 
-    [implementation] => (object value omitted)
-    [documentElement] => (object value omitted)
-    [actualEncoding] => 
-    [encoding] => 
-    [xmlEncoding] => 
-    [standalone] => 1
-    [xmlStandalone] => 1
-    [version] => 1.0
-    [xmlVersion] => 1.0
-    [strictErrorChecking] => 1
-    [documentURI] => %s
-    [formatOutput] => 
-    [validateOnParse] => 
-    [resolveExternals] => 
-    [preserveWhiteSpace] => 1
-    [recover] => 
-    [substituteEntities] => 
-    [firstElementChild] => (object value omitted)
-    [lastElementChild] => (object value omitted)
-    [childElementCount] => 1
-    [nodeName] => #document
-    [nodeValue] => 
-    [nodeType] => 9
-    [parentNode] => 
-    [childNodes] => (object value omitted)
-    [firstChild] => (object value omitted)
-    [lastChild] => (object value omitted)
-    [previousSibling] => 
-    [nextSibling] => 
-    [attributes] => 
-    [ownerDocument] => 
-    [namespaceURI] => 
-    [prefix] => 
-    [localName] => 
-    [baseURI] => %s
-    [textContent] => 
+--EXPECT--
+object(DOMDocument)#1 (39) {
+  ["config"]=>
+  NULL
+  ["dynamicProperty"]=>
+  object(stdClass)#2 (0) {
+  }
+  ["doctype"]=>
+  NULL
+  ["implementation"]=>
+  string(22) "(object value omitted)"
+  ["documentElement"]=>
+  string(22) "(object value omitted)"
+  ["actualEncoding"]=>
+  NULL
+  ["encoding"]=>
+  NULL
+  ["xmlEncoding"]=>
+  NULL
+  ["standalone"]=>
+  bool(false)
+  ["xmlStandalone"]=>
+  bool(false)
+  ["version"]=>
+  string(3) "1.0"
+  ["xmlVersion"]=>
+  string(3) "1.0"
+  ["strictErrorChecking"]=>
+  bool(true)
+  ["documentURI"]=>
+  string(46) "/run/media/niels/MoreData/php-src-FOR-MERGING/"
+  ["formatOutput"]=>
+  bool(false)
+  ["validateOnParse"]=>
+  bool(false)
+  ["resolveExternals"]=>
+  bool(false)
+  ["preserveWhiteSpace"]=>
+  bool(true)
+  ["recover"]=>
+  bool(false)
+  ["substituteEntities"]=>
+  bool(false)
+  ["firstElementChild"]=>
+  string(22) "(object value omitted)"
+  ["lastElementChild"]=>
+  string(22) "(object value omitted)"
+  ["childElementCount"]=>
+  int(1)
+  ["nodeName"]=>
+  string(9) "#document"
+  ["nodeValue"]=>
+  NULL
+  ["nodeType"]=>
+  int(9)
+  ["parentNode"]=>
+  NULL
+  ["childNodes"]=>
+  string(22) "(object value omitted)"
+  ["firstChild"]=>
+  string(22) "(object value omitted)"
+  ["lastChild"]=>
+  string(22) "(object value omitted)"
+  ["previousSibling"]=>
+  NULL
+  ["nextSibling"]=>
+  NULL
+  ["attributes"]=>
+  NULL
+  ["ownerDocument"]=>
+  NULL
+  ["namespaceURI"]=>
+  NULL
+  ["prefix"]=>
+  string(0) ""
+  ["localName"]=>
+  NULL
+  ["baseURI"]=>
+  string(46) "/run/media/niels/MoreData/php-src-FOR-MERGING/"
+  ["textContent"]=>
+  string(12) "
     foobar
-
-)
+"
+}
diff --git a/ext/dom/tests/gh11791.phpt b/ext/dom/tests/gh11791.phpt
new file mode 100644
index 00000000000..22d94b51312
--- /dev/null
+++ b/ext/dom/tests/gh11791.phpt
@@ -0,0 +1,39 @@
+--TEST--
+GH-11791 (Wrong default value of DOMDocument.xmlStandalone)
+--EXTENSIONS--
+dom
+--FILE--
+<?php
+$doc = new DOMDocument();
+$doc->loadXML('<root/>');
+var_dump($doc->xmlStandalone);
+$doc->xmlStandalone = true;
+var_dump($doc->xmlStandalone);
+
+$doc = new DOMDocument();
+$doc->loadXML('<?xml version="1.0"?><root/>');
+var_dump($doc->xmlStandalone);
+$doc->xmlStandalone = true;
+var_dump($doc->xmlStandalone);
+
+$doc = new DOMDocument();
+$doc->loadXML('<?xml version="1.0" standalone="no"?><root/>');
+var_dump($doc->xmlStandalone);
+$doc->xmlStandalone = true;
+var_dump($doc->xmlStandalone);
+
+$doc = new DOMDocument();
+$doc->loadXML('<?xml version="1.0" standalone="yes"?><root/>');
+var_dump($doc->xmlStandalone);
+$doc->xmlStandalone = false;
+var_dump($doc->xmlStandalone);
+?>
+--EXPECT--
+bool(false)
+bool(true)
+bool(false)
+bool(true)
+bool(false)
+bool(true)
+bool(true)
+bool(false)