| John Nielsen | |
| Birth Date: | 26 March 1946 |
| Birth Place: | Denmark |
| Position: | Forward |
| Clubs1: | B 1901 |
| Clubs2: | Göztepe A.Ş. |
| Clubs3: | FC Bremerhaven |
| Nationalteam1: | Denmark U-21 |
| Nationalcaps1: | 1 |
John Nielsen (born 26 March 1946) is a Danish former footballer who played as a forward, finishing the top goalscorer of the 1971 and 1972 Danish football championships for B 1901. He played one game for the Denmark national under-21 football team. He moved abroad to play professionally for Göztepe A.Ş. and FC Bremerhaven.