Robert Kempainen (born June 18, 1966, in Minneapolis, Minnesota) is an American retired two-time Olympian long-distance runner.
He participated in the 1992 (Barcelona, Spain) and in 1996 (Atlanta, United States) Olympics.
He was the 1996 Olympic Trials Marathon (held in Charlotte, North Carolina) champion, winning in a time of 2:12:45.
In other USA distance running championships, Kempainen was also the 1990 US National Cross Country Champion.
A graduate of Dartmouth College and University of Minnesota Medical School, Dr. Kempainen currently holds a position at Hennepin County Medical Center where he practices as a pulmonologist and critical care physician, he is also the current course director of Human Health and Disease 1, a second year medical school course at the University of Minnesota.