Jacek Kamil Krzynówek (Polish pronunciation: [ˈjatsɛk kʂɨˈnuvɛk]; born 15 May 1976) is a Polish former professional footballer who played as a midfielder.

He is regarded as one of the best Polish footballers. He has earned many awards and trophies, not only in Poland, but also abroad. He has earned the honour of twice being named the Polish Footballer of the Year by magazine Pilka Nozna in 2003 and 2004. He has appeared in 96 international matches for Poland, scoring 15 goals. He is also a member of the Elite Poland national team Footballers by the PZPN.

One of his career highlights of his career was scoring a highly acclaimed goal against Real Madrid in the 2004–05 UEFA Champions League.

Krzynówek's football career started with LZS Chrzanowice. In 1994 he joined RKS Radomsko where he played two seasons and then moved to another Polish club, Raków Częstochowa, in which he made his debut on 28 July 1996 in the Polish Ekstraklasa.

After a season with Raków, he moved to second division club, GKS Bełchatów. In the 1997–98 season, he with his team advanced to the Ekstraklasa. His club was unable to keep itself in the top division, and was relegated to the second division. Despite this, his skills and play impressed scouts from other clubs, including 1. FC Nürnberg, as well as the coach of the Poland national team, Janusz Wójcik.