Socialist Party of Aragon (in Spanish: Partido Socialista de Aragón) was a democratic socialist political party in Aragón, Spain.

PSA was formed in 1976 by the Socialist Alliance of Aragón, members of the magazine and cultural group Andalán and independents close to socialist Aragonesism.

The party was formed in the home of Ángela Abós Ballarín.

The Aragonese section of Socialist Reconstruction, a group of members of the Unión Sindical Obrera trade union, also joined the party later.

Other members of the party, from the more radical and nationalist wing, formed the Nationalist Movement of Aragón the same year, along with people from the Rolde de Estudios Nacionalistas Aragonés association.