A 25-year-old Oxon Hill man was convicted yesterday of killing Howard University professor and restaurateur Yossi B.B. Mushala last year.

A D.C. Superior Court jury convicted Michael B. Hutchinson of first-degree murder while armed, and of armed robbery. Judge Robert A. Shuker set sentencing for May 9.

Mushala, a native of Tanzania who owned the Kenyon Grill in Northwest Washington, was killed by a blast from a sawed-off shotgun after two men announced a robbery inside the grill and ordered everyone to lie on the floor.

All but Mushala obeyed. According to court testimony, Mushala, who translated farming news for the Voice of America and whose voice was known to millions of Africans, reached out to the gunman and said: "Please, young man, can we talk about it?"

The gunman, according to testimony, responded by shooting Mushala in the abdomen. The two bandits emptied the grill's cash register of $180 and took a roll of bills from Mushala's pocket.

Employes and patrons of the grill identified Hutchinson as the gunman. Hutchinson testified that he was home the night Mushala was shot. Police are searching for two other men who allegedly assisted in the robbery and getaway.