Robert Lee Nieman (born October 21, 1947) is an American modern pentathlete who competed at the 1976 and 1988 Summer Olympics.

[1] Nieman won the 1979 World Pentathlon Championship, and remains the only American man to capture a world title.

He was one of 461 athletes to receive a Congressional Gold Medal instead.

[2] Nieman won a team silver medal in épée fencing event at the 1983 Pan American Games.

This biographical article related to modern pentathlon in the United States is a stub.