There have to date been many reports of the application of measurement of racemization of amino acids to estimation of the dates of fossil bones. In most of these studies, Asp was used as the indicator for estimation of the date, although racemization of other amino acids was used in some studies. It is uncertain whether Glu and Ala are possible as indicators for age estimation through the use of racemization rates. The current study compared the degree of racemization of each amino acid and the accuracy of the ages estimated from them. Specimens were obtained from males aged 16-79 years. Each specimen consisted of the compact material of the femur of 21 cadavers. The femur was transected at its middle portion with a cutter, and a slice of bone was removed. This report describes the computation of the equation for the reaction rate of racemization of each amino acid. The degrees of racemization were found to differ between the three amino acids depending on the fraction tested. The correlation coefficient between the degree of racemization and the chronological age was higher in the SP than in the TAA or IC fraction. As predicted, among the three amino acids, Asp showed the highest correlation coefficient. The technical logistics were also the easiest to perform with Asp. 8 figures and 33 references