Four new carbazole alkaloids, murrayamines F-H and euchrestifoline, were isolated from the leaves of Murraya euchrestrifolia in May. The variation of carbazole alkaloids in the leaves with seasons was also examined and the results obtained could be used to explain that the pharmacological activity of the plant in traditional Chinese medicines is strictly related to the collection time. Neither coumarins nor flavonoids were found in M. euchrestifolia and supported Tanaka's proposition to divide Murraya into two sections, Murraya and Bergera.