Five alkaloids, 5,6-dihydro-6-methoxynitidine (1), dictamnine (2), gamma-fagarine (3), skimmianine (4), and 5-methoxydictamnine (5), were isolated from the roots of Zanthoxylum nitidum. Their structures and configurations were elucidated by spectroscopic methods and X-ray analysis. Compounds 1, 4,