The speed of ultrasound (SOS) in right middle tibia and bone mineral density (BMD) of left radius at the distal one-third were measured by ultrasonic measurement and single photoabsorptionmetry in 260 healthy individuals simultaneously. SOS of tibia was positively correlated with BMD of radius (r = 0.64). The peak bone mass of both measurements was at 33 to 36 years of age. Height was positively correlated with the SOS of tibia, while weight was positively correlated with SOS of female tibia, period of menopause negatively correlated with female's SOS of tibia. The concordance of SOS of tibia and BMD of radius in diagnosis of osteoporosis was 36.8%. The results suggest that ultrasonic measurement of tibia is an effective method of bone mass measurement.