Sixteen alkaloids have been isolated from the fruits of Kopsia officinalis Tsiang and P. T. Li (Apocynaceae), a plant commonly used in folk medicine for treating tonsillitis and rheumatism. Ten of them were identified as known alkaloids — eburnamenine (1), kopsanone (2), 5, 18‐dioxokopsan (3), kopsinilam (4), kopsinine (5), pleiocarpine (6), kopsamine (7), N‐carbomethoxy‐12‐methoxykopsinaline (8), N‐carbomethoxy‐11, 12‐dimethoxykopsinaline (9) and (+)‐vincadifformine (13). The other three have now been proved to be new. They are N‐carbomethoxy‐11‐hydroxy‐12‐methoxy‐kopsinaline (10), N‐carbomethoxy‐11‐methoxy‐12‐hydroxykopsinaline (11) and kopsamine N‐oxide (12). Copyright © 1989 SIOC, CAS, Shanghai & WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim