The resolutions of both enantiomers of the ornidazole and sec-nidazole were achieved with high enantiomeric excesses (ee>99%) by acylation of the corresponding racemates with vinylac-etate in the presence of lipase Amano AK (from Pseudomonassp.). The assignments of the absolute configurations of (+) or(-)-ornidazole and secnidazole are described. The resolutions of both enantiomers of the ornidazole and sec-nidazole were achieved with high enantiomeric excesses (ee> 99%) by acylation of the corresponding racemates with vinylac-etate in the presence of lipase Amano AK (from Pseudomonas p.). The assignments of the absolute configurations of (+) or (-) - ornidazole and secnidazole are described.