With the indirect immunobead antisperm antibody test(IBT) a prospective study was conducted to evaluate the immune status of 38 men before and after vasovasostomy. The pregnancy and postoperative semen analysis were evaluated. The results were compared between pregnant (n=14) and non-pregnant(n=24) group. The postoperative sperm motility was inversely correlated with the titer of the preoperative and postoperative IgG(p<0.01). The preoperative and postoperative titer of IgG were significantly higher than the titer of IgA or IgM(p<0.05). The mean percentage of the positive IBT(20 per cent binding or more) of the pregnant group was significantly lower than non-pregnant group in the preoprative and postoperative IgG(p<0.05). Immunobead binding restricted to the head and tail of a sperm in IgG was predominant and significantly lower in the pregnant group (p<0.05). In conclusion, IgG especially immunobead binding to the head and tail can be used as a sensitive screening assay for antisperm antibodies after vasovasostomy.