He faces up to nine years in prison, the Los Angeles Times reported.
But Campbell's family and supporters treated Friday's split verdict as a vindication. He led the city from 1994 to 2002 and was mayor during the 1996 Olympic Games.
"God is good," Mildred Campbell Christmas, Campbell's sister, said. "We all prayed hard."
Federal prosecutors charged that Campbell exchanged city contracts for cash and gifts, including campaign contributions. They tried to show a pattern of high living that did not match Campbell's income, including a month in 1999 when Campbell vacationed in Puerto Rico and visited Miami and Paris, while withdrawing only $69 from his personal checking account.
The case was racially charged with Campbell's supporters saying he was targeted because he is black. During jury selection, the judge admonished both sides for dismissing jurors because of race.