This study was designed to investigate the optimum recommendation level on Gatrodia rhizoma and the effects on the improvement of the lipids in the dietary hypercholesterterolemic rats. Experimental diets mixed with 5% Dioscorea batatas(Group 2), 10% Dioscorea batatas(Group 3), 15% Dioscorea batatas (Group 4) 5% Gastrodia rhizoma (Group 5), 10% Gastrodia rhizoma (Group 6), and 15% Gastrodia rhizoma (Group 7), were administered to the male rats of the Sprague Dawley for 3 weeks. Concentration of total cholesterol in serum was lower in the Gastrodia rhizoma groups than in the other groups, especially total cholesterol concentration of 10% Gastrodia rhizoma(Group 6) was the lowest in the Gastrodia rhizoma groups. Concentration of HDL-cholesterol in serum was higher in the 10% Gastrodia rhizoma and 15% Gastrodia rhizoma than in the other groups. Concentrations of cholesteryl ester, LDL, LDL-cholesterol in serum were the lowest in the 10% Gastrodia rhizoma. Concentration of glucose and activity of GPT in serum were the lowest in the 10% Gastrodia rhizoma group. The activity of GOT in serum was lower in the 10% Gastrodia rhizoma group and 15% Gastrodia rhizoma group than in the other groups. Therefore, we consider that there are effects on the improvement of the lipids in the Gastrodia rhizoma and the optimum recommendation quantity of Gastrodia rhizoma is 10% to quantity of food composition.