diff --git a/includes/api/ApiOptions.php b/includes/api/ApiOptions.php
index 265c2ccb674..01a376073f3 100644
--- a/includes/api/ApiOptions.php
+++ b/includes/api/ApiOptions.php
@@ -74,13 +74,36 @@ class ApiOptions extends ApiBase {
 		}
 
 		$prefs = Preferences::getPreferences( $user, $this->getContext() );
+
+		// Multiselect options are stored in the database with one key per
+		// option, each having a boolean value. Extract those keys.
+		$multiselectOptions = array();
+		foreach ( $prefs as $name => $info ) {
+			if ( ( isset( $info['type'] ) && $info['type'] == 'multiselect' ) ||
+					( isset( $info['class'] ) && $info['class'] == 'HTMLMultiSelectField' ) ) {
+				$options = HTMLFormField::flattenOptions( $info['options'] );
+				$prefix = isset( $info['prefix'] ) ? $info['prefix'] : $name;
+
+				foreach ( $options as $value ) {
+					$multiselectOptions["$prefix$value"] = true;
+				}
+
+				unset( $prefs[$name] );
+			}
+		}
+
 		foreach ( $changes as $key => $value ) {
-			if ( !isset( $prefs[$key] ) ) {
+			if ( isset( $prefs[$key] ) ) {
+				$field = HTMLForm::loadInputFromParameters( $key, $prefs[$key] );
+				$validation = $field->validate( $value, $user->getOptions() );
+			} elseif( isset( $multiselectOptions[$key] ) ) {
+				// A key for a multiselect option.
+				$validation = true;
+				$value = (bool)$value;
+			} else {
 				$this->setWarning( "Not a valid preference: $key" );
 				continue;
 			}
-			$field = HTMLForm::loadInputFromParameters( $key, $prefs[$key] );
-			$validation = $field->validate( $value, $user->getOptions() );
 			if ( $validation === true ) {
 				$user->setOption( $key, $value );
 				$changed = true;
diff --git a/tests/phpunit/includes/api/ApiOptionsTest.php b/tests/phpunit/includes/api/ApiOptionsTest.php
index ac18afe7aa8..b30b356e46b 100644
--- a/tests/phpunit/includes/api/ApiOptionsTest.php
+++ b/tests/phpunit/includes/api/ApiOptionsTest.php
@@ -63,6 +63,22 @@ class ApiOptionsTest extends MediaWikiLangTestCase {
 			);
 		}
 
+		$preferences['testmultiselect'] = array(
+			'type' => 'multiselect',
+			'options' => array(
+				'Test' => array(
+					'<span dir="auto">Some HTML here for option 1</span>' => 'opt1',
+					'<span dir="auto">Some HTML here for option 2</span>' => 'opt2',
+					'<span dir="auto">Some HTML here for option 3</span>' => 'opt3',
+					'<span dir="auto">Some HTML here for option 4</span>' => 'opt4',
+				),
+			),
+			'section' => 'test',
+			'label' => '&#160;',
+			'prefix' => 'testmultiselect-',
+			'default' => array(),
+		);
+
 		return true;
 	}
 
@@ -262,4 +278,36 @@ class ApiOptionsTest extends MediaWikiLangTestCase {
 
 		$this->assertEquals( self::$Success, $response );
 	}
+
+	public function testMultiSelect() {
+		$this->mUserMock->expects( $this->never() )
+			->method( 'resetOptions' );
+
+		$this->mUserMock->expects( $this->at( 1 ) )
+			->method( 'setOption' )
+			->with( $this->equalTo( 'testmultiselect-opt1' ), $this->equalTo( true ) );
+
+		$this->mUserMock->expects( $this->at( 2 ) )
+			->method( 'setOption' )
+			->with( $this->equalTo( 'testmultiselect-opt2' ), $this->equalTo( false ) );
+
+		$this->mUserMock->expects( $this->at( 3 ) )
+			->method( 'setOption' )
+			->with( $this->equalTo( 'testmultiselect-opt3' ), $this->equalTo( false ) );
+
+		$this->mUserMock->expects( $this->at( 4 ) )
+			->method( 'setOption' )
+			->with( $this->equalTo( 'testmultiselect-opt4' ), $this->equalTo( false ) );
+
+		$this->mUserMock->expects( $this->once() )
+			->method( 'saveSettings' );
+
+		$request = $this->getSampleRequest( array(
+			'change' => 'testmultiselect-opt1=1|testmultiselect-opt2|testmultiselect-opt3=|testmultiselect-opt4=0'
+		) );
+
+		$response = $this->executeQuery( $request );
+
+		$this->assertEquals( self::$Success, $response );
+	}
 }