This paper deals with the correlation between age and hyperchromic effect of alkali denaturated DNA as well as with the effect of the compound on the hyperchromic effect of alkalied denaturated DNA of old rats or mice. The result shows that the hyperchromic effect of alkalied denaturated DNA in the liver of old rats or mice is obviously higher than that of the young rats or mice respectively(P < 0.01),the hyperchromic effect of alkalied denaturated DNA in the liver of old rats or mice fed with the compound is distinctly lower than that of ather old rats or mice fed without the compound (P