Advanced composite material has been widely used in aviation industry because of good performances. As manual forming prevails in China’s composite manufacturing, study of automatic manufacturing on large-sized stiffened panel has significant importance in promoting China’s composite manufacturing industry. This paper focuses on the study of manufacturing of center-wing-box lower panel of an aircraft, verifies automatic manufacturing flow with combination of automated tape layup, hot drape forming, automatic turn-over, which provides a foundation for establishment of future composite automatic manufacturing line.