Benzino, whose real name is Raymond Scott, 48, was in his red Dodge SUV in route to St. Peter's Church in Plymouth, Mass., when he was shot.
Police said Benzino's nephew, Gai Scott, 36, pulled up beside the rapper in his Bentley and fired shots.
Scott was arrested on charges of armed assault with attempt to murder.
Benzino was treated at South Shore Hospital and the funeral for his mother, though late, went on as planned.
Benzino, star of Love & Hip-Hop Atlanta, posted a photo of himself at the hospital with his arm bandaged.
[New York Daily News]