In a group of 166 type II diabetics hospitalized in a medical department the authors made clinical and ultrasonographic examinations focused on the presence of cholecystolithiasis. The control group was formed by 67 subjects with normal glucose tolerance. None of the patients were hospitalized on account of biliary disease. The purpose of the work was to 1. evaluate the difference in the incidence of cholecystolithiasis in diabetic patients and controls with regard to age and sex, 2. to assess differences in the incidence of obesity, impaired lipid metabolism and a positive biliary family--history in diabetics and controls with lithiasis, 3. to evaluate diabetes and the presence of microalbuminuria. In the authors' group cholecystolithiasis is significantly more frequent in diabetics as compared with controls, in men, women and people above 65 years (p less than 0.01). The group of diabetics and controls with lithiasis does not differ as to the incidence of obesity, hyperlipoproteinaemia and positive family-history of biliary disease. No significant differences in parameters of compensation of diabetes nor differences in the incidence of microalbuminuria were found between diabetics with and without lithiasis. The results suggest that it is useful to screen cholecystolithiasis in diabetic subjects.