It was founded in 1956 by Justin Catayée, beforehand the founder of the Guianese federation of the French Section of the Workers' International (SFIO).
For instance, the PSG endorsed the overseas list of Europe Ecology – The Greens, not the PS one, in the 2004 European elections.
The PSG didn't compete as such for the December 2015 first Guianese Assembly elections after the merger of the department and the region, and the coalition list it supported, headed by deputy Chantal Berthelot from another left-wing party, got only 8.49% and was eliminated at the first round.
For the first elections to the Guianese Assembly in December 2015, the PSG did not compete as such but on a common list Cultiver la Guyane led by the deputy Chantal Berthelot of the party To the Left in Guiana (AGEG).
[4] Only two lists could compete for the second round and both their leaders refused any merger with lists that had got between 5% and 10% for the first round, thus eliminating from the new assembly the PSG, but also all the other parties hitherto represented in one or both previous councils: AGEG, Walwari (Christiane Taubira's party), MDES and LR.