The ejaculates from 67 HanWoo prove bull, bred in Livestock Improvement Main center of NLCF, were used to determine the correlation between the sperm motional characteristics and the pregnancy rate of artificial insemination(AI). The motional characteristics of sperm were analysed by Computer-assisted sperm analyser(CASA), thereafter inseminated equally 1,256 heads of cow regarding to parity, age, and live weight. There were no significant difference(p>0.05) in the pregnancy rate according to year from 1996 to 1998, but the LIN, ALH, STR, BCF, MAD and WOB of sperm in the year 1997, were highest pregnancy rate, were higher than those of sperm in the year 1998, were lowest pregnancy rate(p<0.05). The semen had no significant effect on pregnancy rate according to season(p>0.05). However spring, had a little higher pregnancy rate than that of autumn, were higher than autumn in VSL, VAP, LIN, ALH, BCF, MAD and WOB, but in DNM. The pregnancy rates of spring in the year 1996 and 1997 were higher than that of autumn in the year 1998(p<0.05). The spring in the year 1997, highest in pregnancy rate, were higher than the autumn in the year 1998 in VSL, VAP, LIN, STR, BCF, MAD and WOB, but in DNM(p<0.05). There were no the motion characteristic of sperm that was significant correlate with pregnancy rate of AI as the semen were analysed before artificial insemination and those, had some degree characteristics in motility, viability and abnormality, were used to AI. However there were a tendency that the higher the VSL, VAP, ALH, LIN, STR, BCF, MAD and WOB and the lower the DNM were, the higher the pregnancy rate of AI were.