Summary: Diabetes mellitus is a metabolic disease characterized by hyperglycemia that leads to damage, dysfunction, and failure of various organs. It is a progressive disease, leading to chronic complications and deterioration of the quality of life, and an increase in mortality due to cardiovascular diseases. Therefore, screening for diabetes should be performed in all patients over the age of 65, and an elderly patient diagnosed with diabetes should be provided with individual treatment and a care plan. The general principles of diabetes treatment, in this case, are similar to those in the younger age groups. Doctors can use virtually all groups of anti-diabetic drugs but should pay particular attention on their side effects, and above all, to the risk of hypoglycemia. Treating physicians should also remember not to correct hyperglycemia too rapidly, and the established therapeutic goals ‒ adjusted to the health situation of an elderly patient ‒ should be achieved gradually.