The purpose of this research was to analyse the change in relationships between the basic carbohydrate and lipid metabolisms parameters in the cardiac muscle and liver in the animals with diabetes, in which the thyroidal hypofunction was evoked additionally. The tests were performed on 43 white rats of the Wistar breed that were subdivided into four groups. The first group were reference animals. The second group were the animals with the evoked thyroidal hypofunction with metizol. The group three rats were injected a single dose of alloxan each in order to evoke diabetes. In group four, diabetes and the thyroidal hypofunction were evoked. The levels of glycogen, lactic and pyruvic acids, cholesterol, free fatty acids, triglycerides and phospholipids were determined in the cardiac muscles and livers of all the animals. It was found that the occurrence of both hormonal disorders, i.e. diabetes and the thyroidal hypofunction, in short time leads to harmful changes in the lipid metabolism of the cardiac muscle and liver and noticeably reduces the glycogen reserve in the liver.