The chloroform extracts of the air-dried leaves of Catharanthus roseus Linn. afforded perivine (1). The structure of 1 was elucidated by 10 and 20 NMR, UVand FT-IR spectroscopy and mass spectrometry. Results of the antimicrobial tests on 1 showed that at a concentration of 20 mg, 1 is active against Pseudomonas aerugenosa, Bacillus subtilis, Candida albicans and T. mentagrophytes. It was found inactive against Aspergillus niger, Escherichia coli and Staphylococcus aureus.