RESUMEN
The ABO blood group antigens in the spermatozoa from 40 donors were studied using the indirect immunofluorescence method.Group A antigens in the spermatozoa from group A donors and group B antigens in the spermat- ozoa from group B donors were detected.Some of the spermatozoa from group AB donors carry the A antigens and others carry the B antigens.The spermatozoa from four ABO blood group donors all carry H antigens.The blood group antigens in the spermatozoa are inherent,not from the seminal plasma.The amount of ABO blood group antigens from different individuals was different and was independens of the secrete status and the amount of ABH substances in the secretor's seminal plasma.The ABO blood group antigens of spermatozoa were mainly distributing in the regions of spermat- ozoals neck and acrosome.