INTRODUCTION: The aim of our study was to assess the influence of cardiovascular complications on the occurrence of late ventricular potentials (LP) in children with diabetes mellitus type 1. MATERIALS AND METHODS: 72 children (36 boys and 36 girls), with average course of diabetes type 1 of 6.5+/-2.8 years, were included into the study. Standard physical examination, blood pressure measurements, signal-averaged electrocardiogram (SAECG), autonomic test, 24-h Holter monitoring, and Doppler echo investigations were performed. The control group consisted of 55 sex- and age-matched healthy children. We utilised nonlinear logistic regression analysis to assess the effect of disease duration, albuminuria, insulin demand, cardiac autonomic neuropathy (CAN), heart rate variability (HRV) indices, diabetes complication score, metabolic control, systolic and diastolic blood pressure, left ventricular parameters, and ventricular arrhythmias on LP occurrence. RESULTS: LP was discovered in 12 patients with diabetes and in 1 from the control group (P<.014). Diabetic children with LPs had thicker left ventricular posterior wall (LVPW) and longer diabetes duration time than children without LP (P<.045 and.031, respectively). Nonlinear regression model shows that duration of diabetes, CAN, and LVPW were the strongest independent parameters of LP occurrence (P<.001,.01 and.005, respectively). CONCLUSIONS: Diabetes type 1 is associated not only with increased occurrence of abnormal SAECG but also with LP presence. The disease duration, posterior wall thickness, and CAN are independent predictors of LP appearance in diabetes type 1 children. The presence of cardiovascular complication has no influence on LP occurrence in diabetic children.