Right-left differences in the maximum length of the humerus and radius, and the femur and tibia of the leg in an archaic population were investigated. The materials consisted of skeletons dated to the Neolithic Jomon period excavated in eastern Japan. The results obtained in this study were compared with those of four other populations. Dominant side in the arm and leg bones were found to be dissimilar based on the mean right-left differences. The arm bones of right side were significantly longer than those of left. The leg bones of the left side were longer than those of the right. Mean right-left differences of female arm bones were usually greater than those of males. Obvious sex-differences could not be seen for leg bones. The mean right-left differences of the humerus seemed to be more variable than those of the other three bones.