OBJECTIVE: Patients with mild autonomous cortisol secretion (MACS) are at increased risk of cardiometabolic outcomes, such as hyperglycemia, metabolic syndrome, and cardiovascular diseases. Nonalcoholic fatty liver disease (NAFLD) is also associated with increased cardiometabolic risk. We aimed to investigate the prevalence and predictors of NAFLD in metabolically healthy subjects with MACS. METHODS: Forty patients with MACS and 60 patients with nonfunctioning adrenal incidentaloma (NFAI) matched for age, gender, and body mass index were included. We excluded various diseases that may lead to NAFLD, such as diabetes, cardiovascular diseases, and liver disorders. Non-alcoholic fatty liver disease was evaluated with unenhanced abdominal computed tomography and noninvasive fatty liver indices. RESULTS: Patients with MACS had lower mean liver attenuation values (Hounsfield units, HU) than those with NFAI (p = 0.002). Visceral adiposity index, hepatic steatosis index, and fatty liver index were higher in the MACS group than in the NFAI group (p = 0.009, p = 0.002, p = 0.023, respectively). However, there was no significant association between the mean liver HU value and these indices. There was a significant association between serum cortisol level after the 1 mg dexamethasone suppression test (DST) and mean liver HU value independent of other traditional risk factors in various models performed in multivariable linear regression analysis. CONCLUSIONS: Our findings suggest that MACS is associated with an increased risk of NAFLD, and serum cortisol level after 1 mg DST is an independent predictor of NAFLD in patients with MACS.