Labour Popular Socialist Party was a political party in the Russian Empire. It was formed after a split from the Socialist-Revolutionary Party in 1906. The party stood for a bloc with the Cadet Party, earning them the nickname "Social-Cadets".
During World War I the party took a social-chauvinist stand. After the February revolution of 1917 the Popular Socialist Party merged with the Trudoviks and actively supported the Provisional Government, in which it was represented. After the October Revolution the party participated in plots and armed acts against the Soviet government. The party dissolved during the Russian Civil War of 1918-1922.