John Hamann Nunn (born October 12, 1942) is an American rower who competed in two Olympics.

He won a bronze medal in the 1968 Summer Olympics with his partner Bill Maher in the double sculls event.

He went on to coach the 1976 Olympic U.S. rowing team in Montreal placing 5th.

A graduate of Cornell University, Nunn was inducted into the Cornell Big Red hall of fame in 2008.

This article about a rowing Olympic medalist of the United States is a stub.