Background: Hypomagnesaemia is common in adult patients with both Type 1 Diabetes Mellitus (T1DM) and Type 2 Diabetes MellitusT2DM, especially in poorlycontrolled and chronically treated adults. However, to our knowledge, little research has addressed the relationship between serum magnesium levels and diabetes in children. The aim of the present study was to evaluate magnesium levels and examine their possible association with glycemic control in children with T1DM.