Democratic Socialist Left (Italian: Sinistra Socialista Democratica, SSD) was a political party in San Marino, founded as an electoral list for the 2016 general election, including United Left, Progressives and Reformists and Democratic Laboratory.

[3] The coalition won the 2016 general election, defeating the ruling coalition San Marino First (formed by the Sammarinese Christian Democratic Party, the Party of Socialists and Democrats, the Socialist Party and the Sammarinese list), while the SSD list won 14 seats in the Grand and General Council.

On 17 November 2017 the first congress of Democratic Socialist Left was celebrated, officially merging the three parties into a single political entity and electing Michele Muratori as party president and Eva Guidi as secretary.

[4] In October 2018 Guidi stepped down as party secretary to join the Sammarinese Government; she was replaced in November by Alessandro Bevitori.

[5] On 30 December 2020, the Democratic Socialist Left was dissolved in order to merge into the Libera San Marino party.