The Yemeni Socialist Party (YSP) is a socialist political party in Yemen that was the ruling party of South Yemen during the Cold War. The party was founded in 1978 by Abdul Fattah Ismail, Ali Nasser Muhammad, and Ali Salim al-Beidh to replace the National Liberation Front, and it adhered to Marxism-Leninism, governing South Yemen as a communist state. After the reunification of Yemen in 1990, the party changed its platform to democratic socialism instead of communism, and it won 8/301 seats in the House of Representatives in 2016.