"Following the opening of the new parliament, a joint session of the House of Representatives and House of Federation elected Ambassador Dr Mulatu Teshome as the President of Ethiopia," the foreign ministry said in a statement.
While officially head of state, real power rests in the hands of the Prime Minister Hailemariam Desalegn.
Mulatu, 57, who was Ethiopia's ambassador to Turkey until his appointment, replaces 88-year old Girma Wolde Giorgis, who first took the post in 2001 and was reelected in 2007.
He has also served as Ethiopia's ambassador to China and Japan as well as Ethiopia's Minister of Agriculture.