The Socialist Party (Portuguese: Partido Socialista, pronounced [pɐɾˈtiðu susiɐˈliʃtɐ]) is a centre-left political party of Portugal. It was founded on April 19, 1973 in the German city of Bad Münstereifel, by militants of the Portuguese Socialist Action (Portuguese: Acção Socialista Portuguesa).

José Sócrates, Prime Minister of Portugal, is the leader of the party. The former President of Portugal, Jorge Sampaio, is also a member of the party. The party has currently 121 of 230 seats in the Parliament.

José Sócrates obtained a landslide victory (conquered 77% of the votes) in early October 2004 for the succession of Ferro Rodrigues as Secretary-General of the party. Other candidates for the post were Manuel Alegre and João Soares in a vote by party members.

It is a member of the Socialist International and the Party of European Socialists, and has 7 members in the European Parliament.

The Socialist Party stands out as about a third of its members in the Assembly of the Republic are women.

List of important people