To provide the information necessary for the insurance medicine management plan, price discount rates among the insurance medicines were studied. A total of 2,107 items of insurance medicine of which prices were discounted via governmental inspections of real transactional process of insurance medicine were analysed. The conclusions are as follows; 1. Among the variables relevant to the characteristics of manufacturers, price discount rates of insurance medicines were statistically significant with production rankings of manufacturers, incorporation year, existence of investments by foreign corporation, existence of a research institute, and enrollment in the exchange. And among the variables relevant to the properties of medicines, the number of enrolled items which have the same components, classification, the date of new enrollment, the sales of items, and the number of raw materials in the items were statistically significant. 2. Stepwise multiple regression was done to identify the factors which affect the price discount rates of insurance medicines. The number of enrolled items which have the same components, production rankings of manufactures, classification number (medicines for function of tissue cells), incorporation year(1940-1949), existence of investments by foreign corporations, classification number (anti-germ medicines), number of raw materials In the items, the sales of items, and medicines whose major objective is not treatment were significant variables and the $R^2$-value for these variables was 21.2%. Considering all of the above results, for management of insurance medicines, it seems important that the real transactional prices of insurance medicines should be identified systematically, focusing on the properties which affect the price discount rates of insurance medicines.