Julian Ignacy Nowak (10 March 1865 – 7 November 1946) was a Polish microbiologist and politician who served as prime minister in 1922.

Nowak studied medicine at the Jagiellonian University in 1886–1893, and was a professor there since 1899. In 1921–1922 he was a rector of the university. Being a conservative politician, he served as the Prime Minister briefly in 1922. In the same year he also served briefly as the Minister of Religious Affairs. In 1922–1927 he was a Senator in the Polish Senate.

He was awarded the Commander's Cross of the Order of Polonia Restituta.

Julian Ignacy Nowak was buried in Rakowicki Cemetery.