Othman Ja'afar was a Bornu politcian who was a member of the Northern Nigeria House of Assembly and later became a parliamentary secretary of the ministry of Social Development in Northern Nigeria.
Ja'afar was born on July 7, 1917 to chief Alkali Ja'afar. He was educated at Bornu Provincial School, the Borno Middle School and Katsina Higher College. He began his professional career as a teacher at the Bornu Middle School. During the second world war, he was a member of a volunteer force.
He was a member of the Bauchi Polo Cub and once headed the Bauchi Native Authority's finance committee.