Born in Turzysk in the Second Polish Republic Kowalski will have been forced to move westwards after World War II due to the changing of borders and expulsion of local populations, with his hometown being given to Ukraine. Kowalski started cycling professionally with Budowlani Warszawa between 1954–1955, spent a short spell with Stal Stocznia in 1956, before spending the majority of his career with KK Lechia Gdańsk between 1957–1970. It was while with Lechia he enjoyed his greatest success, winning the Tour de Pologne twice, in 1957 and 1961. and winning the Vuelta a Cuba in 1967. Kowalski died in Gdańsk aged 88, and is buried in the Żydowski cemetery in Chełm, Gdańsk.