Assefa Mezgebu (born June 19, 1978 in Sidamo) is a retired Ethiopian long-distance runner, most known for winning a bronze medal in the 10,000 metres event at the 2000 Summer Olympics. He was also the runner-up at the 2001 World Championships in Athletics, following a bronze medal at the 1999 World Championships in Athletics. He also competed in cross-country running and reached the podium at the IAAF World Cross Country Championships in 1998 and 2000. Assefa Mezgebu is the younger brother of Ayele Mezgebu.