Background: Advanced glycation end products are associated with chronic complications of diabetes mellitus. This glycation process renders many proteins immunogenic. Aim: To detect the presence of antibodies against albumin, collagen and low density lipoprotein glycation products in boys and teenagers with diabetes mellitus. Patients and methods: Thirty one patients with diabetes mellitus type I, aged 11±3.8 years and with a mean duration of disease of 3.7±2.7 years and 31 healthy controls aged 12.4±5.3 years were studied. Antibodies against glycation end products were detected by ELISA and results were expressed as a ratio of the optical density of the glycated protein/optical density of the native protein. Results: Diabetic patients and healthy controls did not have antibodies against albumin glycation end products. Diabetics had higher levels of antibodies than controls for collagen glycation end products (2.6±0.4 and 1.8±0.2 respectively, p< 0.01) and low density lipoprotein glycation end products (3.07±0.92 and 2.2±0.72 respectively, p< 0.05). Conclusions: The biological role of these antibodies is not clear. They could be a depuration mechanism for glycation end products or contribute to chronic complications of diabetes mellitus (Rev Méd Chile 2001; 129: 141-48).