The 1978–79 I liga was the 53rd season of the Polish Football Championship and the 45th season of the I liga, the top Polish professional league for association football clubs, since its establishment in 1927.

The league was operated by the Polish Football Association (PZPN).

The champions were Ruch Chorzów, who won their 13th Polish title.

The season started on 27 July 1978 and concluded on 10 June 1979 (autumn-spring league).

A total of 16 teams participated, 14 of which competed in the league during the 1977–78 season, while the remaining two were promoted from the 1977–78 II liga.