The effects of six kinds of aqueous extracts of Chinese herbal medicine (Astragalus membranaceus, Acanthopanacis senticosi, Panax genseng and Ophiopogon japonicus, P. genseng and Aconitum carmichaeli, Salviae miltiorrhiae, Polyporus umbellatus polysaccharide) on sperm motility characteristics of 30 infertile male volunteers were studied in vitro with a computer-assisted sperm analysis at 15, 60 and 180 min after incubated with the drugs. The results showed that per cent viability, number of progressive motile spermatozoa, curvilinear velocity, average path velocity and amplitude of lateral head displacement were significantly enhanced by A. membranaceus (P < 0.05 or < 0.01), per cent viability, average path velocity and amplitude of lateral head displacement were significantly enhanced by A. senticosi (P < 0.05), but all the above were not affected by P. genseng and O. japonicus, P. genseng and A. carmichaeli, S. miltiorrhiae and P. umbellatus polysaccharide. It is suggested that A. membranaceus and A. senticosi can enhance the motility of human spermatozoa in vitro.