Haplotypes and allele frequencies of 17 Y-chromosomal short tandem repeat (Y-STR) markers were examined using the AmpFlSTR Yfiler PCR Amplification Kit (Applied Biosystems) in a population sample of 1166 Japanese male volunteers in 6 prefectures: Miyagi, Yamagata, Osaka, Tottori, Fukuoka, and Okinawa. A total of 1058 haplotypes were observed from 1166 males, and the most common haplotype detected in 12 males had a frequency of 1.03% and the discrimination capacity was 0.907. The R(ST) analysis showed statistically significant differences between Okinawa and the other subpopulations.