A study was conducted to investigate the influence of kendo exercise on the bone mineral density in male and female university kendo athletes. The subjects were 45 male university kendo athletes and 23 female university kendo athletes. They had an average kendo experience of 13.2 years and 10.0 years. Measurements were performed using an AOS100 (ALOKA Corp.). We measured the speed of sound (SOS), transmission index (TI), and osteo sonoassessment index (OSI). The mean values of SOS, TI, and OSI in male and female university kendo athletes were higher than in the same aged control group and the peak bone mass aged control group.The values of the left heel were significantly higher than that of the right heel in bone mineral density. Body weight was significantly related to bone mineral density in male and female university kendo athletes. These results suggest that regular kendo exercise during youth is effective for the increase in bone mineral density.