The bone mineral density (BMD) has been analyzed in 200 male patients divided in 4 groups of age as follows: (A) 40-49, (B) 50-59, (C) 60-69, and (D) 70 years and above. BMD was measured by using the DEXA technique both in the ultradistal and mediodistal region of radius of the non-dominant side. In addition, the serum levels of testosterone (Ts), dihydrotestosterone (DHT) and 17-beta estradiol (E-2) have also been measured. The data obtained have shown that bone mineral density values are decreasing also in the males with advancing age, and the positive correlation (p < 0.05) of BMD with the E-2 levels also tend to decrease. These results suggest the hypothesis that the true sexual hormones regulating the rhythm of osteogenesis may be the estrogens in the males, too.