Four of the six crew members onboard the aircraft - carrying ammunition for international forces fighting Islamist militants - were killed.
Ammunition could be heard exploding inside the plane as the fire spread, closing the airport. The blaze was put out after about two hours.
Ethiopian troops entered Somalia in 2011 to assist African Union forces.
It is not known yet when the plane got into difficulties, and whether it overshot the runway, or fell short of it.
