Alan Stuart Lowenthal (; born March 8, 1941) is an American politician who served as the U.S. representative for California's 47th congressional district from 2013 to 2023. A member of the Democratic Party, he served as the California state assemblyman for the 54th district from 1998 to 2004 and California state senator from the 27th district from 2004 to 2012. In both posts, Lowenthal represented the city of Long Beach and its surrounding suburbs. On December 16, 2021, Lowenthal announced that he would not seek reelection to Congress.