Abstract: The present invention discloses a rotary cup washing device, comprising a flushing nozzle, a rotary impeller, a swirl outflow member, a fixed head and a water inlet pipe. The flushing nozzle, the rotary impeller, and the swirl outflow member are all provided in the fixed head. The flushing nozzle is connected to an upper part of the rotary impeller, and a lower part of the rotary impeller is correspondingly matched with the swirl outflow member, the flushing nozzle and the rotary impeller are capable for rotating relative to the fixed head under a water discharge action of the swirl outflow member. A lower part of the fixed head is connected to the water inlet pipe, and the water inlet pipe is connected to a pressure source. The present invention is capable of rotating the water to wash the cup in an omnibearing and uniform manner, and the cleaning effect is better.