The prevalence of celiac disease in the general population is 1%, it is more common in patients with type 1 diabetes. Our objective is to determine the prevalence of anti-transglutaminase type IgA antibodies in children with type 1 diabetes. For this, we conducted a descriptive retrospective study, carried out within the laboratory of immunology-serology of the CHU Ibn Rochd of Casablanca. We included all requests for research of anti-transglutaminase type IgA antibodies in children with type 1 diabetes, over a period of 3 years. Our study identified 480 children with type 1 diabetes. The median age was 9 years with extremes of 1 to 14 years, 247 children were male or 51.5% versus 233 female or 48.5%, the sex ratio (M/F) calculated was 1.06. Anti-transglutaminase type IgA antibodies were positive in 70 patients, a prevalence of 14.6%. We compared the seropositive group (n=70) with the seronegative group (n=410). There was no difference between the two groups for age. However, female children were more affected in the seropositive group. This study confirms that celiac disease is common in diabetic patient’s type 1. Early diagnosis of celiac disease is very important to prevent long-term complications. These complications can be prevented by a simple gluten-free diet.