The Communist Party of Western Ukraine (Polish: Komunistyczna Partia Zachodniej Ukrainy, KPZU; Ukrainian: Комуністична партія Західної України, romanized: Komunistychna partiya Zakhidnoyi Ukrayiny) was a clandestine political party in eastern interwar Poland.
According to Timothy D. Snyder, the Communist Party of Western Ukraine was an illegal and conspiratorial organization in interwar Galicia and Volhynia.
Its influence faded away in the 1930s because of Stalin's regime in the USSR and execution of his policies in Ukraine by Pavel Postyshev and Lazar Kaganovich.
At times, the Communist Party of Western Ukraine was split into different wings, a pro-Soviet faction and a more independent one.
By the end of 1928, the CPWU (majority) disbanded itself, and its leaders who expressed regrets because of their "errors" went to the USSR, where they were later repressed.