The All-Ukrainian Congress of Soviets was the supreme governing body of the Ukrainian Soviet Socialist Republic from 1917–38. From 1922 to 1938 the Constitution of the Ukrainian SSR, modeled on the 1918 Russian Constitution, mandated that Congress to be convened at least twice a year. The 1926 Constitution lowered the minimum to once a year.

The Supreme Soviet of the Ukrainian SSR was the supreme soviet and the highest organ of state power of Ukraine when it was known as the Ukrainian SSR, one of the union republics of the Soviet Union. The Supreme Soviet was the sole branch of government in Ukraine, and per the principle of unified power, all state organs were subservient to it. It was established in 1937 replacing the All-Ukrainian Congress of Soviets.