Background: The prevalence of Autoimmune Hemolytic Anemia (AIHA) globally ranges from 5-30%, but relatively high in Asia, 22%. This condition is commonly found among patients with thalassemia. However, no data are available about this disease in Lao PDR. Objective: To determine the proportion of AIHA among Lao children with thalassemia. Methodology: A cross-sectional study was conducted from May to September 2018 in pediatric patients with thalassemia who received blood transfusion at the Children’s Hospital, Vientiane Capital. There were 338 patients included in the study. Data analysis was done using SPSS, and Pearson chi-square was used to compare the two proportions. Finding: We found that the proportion of AIHA was 3.6% (12/336) amongst those with thalassemia with more males than females (3:1). The mean (SD) age was 11.5 ± 3 years old. The older age of patients was significantly associated with AIHA, p=0.001. We also found that patients with transfusion dependent thalassemia were more likely to have AIHA than those who were not. The mean reticulocyte count (%) was significantly higher in patients with AIHA than those without AIHA (8.61±10.57 versus 1.18±1.14, p<0.001). Other variables such as sex, type of thalassemia, age at diagnosis, the frequency of blood transfusion, age at first blood transfusion, blood group and hemoglobin before blood transfusion were not significantly associated with AIHA. Conclusion The proportion of AIHA remains low in Lao children with transfusion dependent thalassemia, but requires further attention to reduce its complications. There is a need to identify factors associated with AIHA among Lao patients with Transfusion Dependent Thalassemia