Abstract : Malnutrition is a common cause of morbidity and mortality in children with Tetralogy of Fallot (TOF), especially in developing country like Indonesia. However there are still limited studies that focus on the correlation between malnutrition and mortality in children with TOF undergoing total corrective surgery. The purpose of this study is to determined the correlation between malnutrition on mortality in TOF patients undergoing total correction. This is a retrospective cross-sectional study using medical records from 2016 to 2019. In this study, majority of mortality was found in male patients (39.3%) while the female’s rate was lower (36.8%). The overall mortality in malnourished patients was 38.3%. Out of 72.34% patients with malnutrition, 73.5% of them were severely malnourished. Around 87.5% children under 5 years old were stunted, 46% of them were underweight, and 39% was wasted. Meanwhile in children above 5 years old, 69.5% was stunted and 12.5% was wasted. Our study shows that malnutrition is significantly correlated to mortality in TOF post corrective surgery (p=0.001; OR :2.12). As one of the significant and potentially treatable pre-operative comorbidity, prevention of malnutrition by early diagnosis is important to reduce the mortality in TOF repair.