AIM: Theory of mind impairments are part of the cognitive morbidities associated with transposition of the great arteries (TGA). We sought to assess core components of social cognition in school-aged children with TGA. METHOD: Thirty-eight children with neonatal corrected TGA (27 males, 11 females; mean age 7y 3mo, SD 1y 2mo) and a comparison group (n=31; 24 males, 7 females; mean age 7y 4mo, SD 1y 1mo) participated in this study. All children completed measures of facial expression recognition, emotion comprehension, and second-order cognitive and affective false-belief tasks. The association of medical pre-, intra-, and postoperative variables with cognitive outcomes was explored. RESULTS: After controlling for potential covariates, children with TGA performed significantly less accurately in the mental category of the emotion comprehension battery (p=0.002) and on second-order affective false-belief tasks (p<0.05). Preoperative variables including an associated ventricular septal defect (p=0.02), a younger age at open-heart surgery (p=0.03), and a prenatal diagnosis of TGA (p=0.02) were significantly associated with better outcomes. INTERPRETATION: School-aged children with TGA display significant impairment on complex affective mental state understanding even though facial expression recognition was generally preserved. Preoperative factors may be important determinants for long-term outcomes after cyanotic congenital heart disease.