The 1963 South Boston 400 was a Grand National (now Nextel Cup) event held at South Boston Speedway on April 14, 1963. Richard Petty dominated the event, leading 325 of the 400 laps in route to a crushing two-lap victory on Jim Paschal and the rest of the field. Eventual season champ Joe Weatherly finished last (16th) after early rear gear issues.