Six benzo[c]phenanthridine alkaloids, corynoline (1), acetylcorynoline (2), corynoloxine (3), luguine (4), 6-oxocorynoline (5), and 12-hydroxycorynoloxine (6) were isolated from the aerial parts of Corydalis incisa, and 6 was isolated for the first time from nature. The structure was elucidated by