Background: Apelin is a novel adipocytokine produced by white adipose tissue that binds the APJ receptor with high affinity. Insulin may have a role in regulation of apelin synthesis and secretion from the adipose tissue. Objective: To investigate blood apelin concentrations in children with type 1 diabetes mellitus (T1DM) and display association of apelin with adiponectin, body mass index (BMI), lipids and insulin sensitivity. Methods: Thirty patients with T1DM and 45 healthy controls were enrolled. Apelin levels were measured along with BMI, lipids, fasting plasma glucose, HbA1c and adiponectin levels. Results: Plasma apelin and adiponectin levels were significantly higher in the diabetic group when compared to controls. No correlation was found between the apelin blood concentrations and adiponectin, BMI, lipids and insulin sensitivity. Conclusions: Children with T1DM have significantly increased circulating apelin levels when compared to healthy controls. However, no significant relation was found between the apelin and BMI, glucose, lipids and adiponectin levels, and also insulin sensitivity.