Founded in 1896, it is one of the oldest still-active parties in Argentina, alongside the Radical Civic Union.

The PS itself was founded in 1896, led by Justo and Nicolás Repetto, thus becoming the first mass party in the country.

[31] Despite this number being well below the 54.1% achieved by Peronist leader Cristina Fernández de Kirchner, the Socialist Party considered the results of the election as significant and a sign of renewed interest by a sector of the population.

[33] For the 2015 general election, the PS entered in coalition with other centre-left and left-wing parties to form the Progresistas (Progressives) front, which endorsed Margarita Stolbizer for the presidency.

[34] Following the 2017 legislative election, the party was left with a single national deputy, Luis Contigiani, and no representatives in the Senate.