The Belarusian Socialist Assembly, BSA (Belarusian: Беларуская сацыялістычная грамада, Belarusian Socialist Hramada, BSH) was a revolutionary party in the Belarusian territory of the Russian Empire. It was established in 1902 as the Belarusian Revolutionary Party, renamed in 1903.
The BSA had branches in Minsk, Vilna and also in St. Petersburg. After the February Revolution in Russia, the political activity in Belarus increased, and in summer of 1917 BSA gave rise to the Communist Party of Byelorussia and the Belarusian Social Democratic Party.
On March 19, 1918 on the initiative of the BSA, the Council (Rada) of the Belarusian National Republic has become a temporary, short-lived parliament in Belarusian lands. Most of the BNR Counsil were members of the BSA.
Russian Bolsheviks had a negative attitude towards the BSA. Vladimir Lenin described BSA as a "nationalist petty bourgeois party of left populist orientation". The 2nd Congress of the Soviets of the Western Province (Russia) declared the Council of the Belarusian Republic counter-revolutionary and anti-Soviet.
- Vaclaw Lastowski, politician and historian;
- Alaiza Pashkievich, writer;
- Jan Sierada, politician;
- Branisłaŭ Taraškievič, linguist;
- Vasil Zacharka, the second president of the Belarusian People’s Republic.