The Romanian Socialist Party (, PSR) is a political party in Romania formed as the Socialist Alliance Party (PAS) in 2003. It grew out of a wing of the Socialist Party of Labour (PSM) that objected to the merger of PSM with the Social Democratic Party in July 2003, and wanted the PSM to continue as a socialist party. Romanian authorities did not recognize this group as part of PSM, and instead made them take the name Socialist Alliance Party.

After absorbing the United Left Party in 2009, PAS was renamed as the Socialist Alternative Party in late 2013. In late 2014, the party changed its name to the Socialist Party of Romania, replacing the party of the same name that became defunct the previous year. The Socialist Party of Romania would adopt a communist program; the unregistered Romanian Communist Party (later known as the Communitarian Party of Romania) opposed this and had argued that the PSR was a "pseudo-communist party". The PSR had previously attempted to rename itself as the Romanian Communist Party at an extraordinary party congress in July 2010, placing itself in the tradition of the original Romanian Communist Party founded in 1921. This renaming was rejected by a tribunal in Bucharest.

In 2013, the party won 34 local seats. The party is led by a 165-member National Committee, a 60-member Directive Committee, and a 60-member Executive Bureau. PSR is a founding member of the Party of the European Left.

Ideology

The Romanian Socialist Party is a communist party and places itself in the tradition of the original Romanian Communist Party. supporting socialist feminism.

The party opposes the current form of the European Union, and considers Romania's involvement in the union as having brought the country more negative consequences than benefits. It has called for the creation of a "Europe of Nations" that would include Russia, and is supportive of European federalism.