Autoimmune diabetes is an organ specific and multifactorial disorder including insulin dependent diabetes mellitus (Type 1 Diabetes) and latent autoimmune diabetes in adults (LADA), which progresses to insulin dependency because of the beta cells destruction. Several polymorphisms in different genes have been associated with diabetes. The CTLA4 gene is considered a down regulator of T cell function, and the SUMO4 gene encodes a small ubiquitin-like modifier implicated in the intensity and duration of the immune response. We selected 62 LADA patients, 123 patients with Type 1 diabetes patients and 136 unrelated volunteers to study CTLA4 -318 C/T, 159 C/T, 3' STR and SUMO4 163 A/G polymorphisms by PCR. There was a statistical difference significant in the frequency of the allele 209pb for the 3'STR between LADA and Type 1 diabetes patients but not with respect the normal group, the frequencies were found to be 6.9%, 1.0% and 1.9%, respectively. However, no association with either of the polymorphisms has been found in the studied population. The knowledge of the several susceptibility loci in autoimmune diabetes will enhanced the prediction of individuals at high risk of developing the disease in order to establish the best treatment and the prevention of autoimmune diabetes.