Background: Metabolic dysfunction–associated steatotic liver disease (MASLD) is the most common pediatric liver disease, yet known biological risk factors do not fully explain its development. This study evaluated the association between social determinants of health (SDH)—including income, education, housing, and environmental factors—and MASLD in children with overweight or obesity. Methods: This cross-sectional study included children with overweight or obesity evaluated in pediatric gastroenterology clinics, stratified by the presence of MASLD. Participants’ residential census tracts were linked to the California Healthy Places Index (HPI), where higher scores indicate greater socioeconomic advantage. Generalized linear regression models, adjusted for age, sex, race, ethnicity, and body mass index (BMI), assessed associations between SDH and MASLD. Results: The study included 888 children (mean age: 12.8±2.9 y, mean BMI: 30.6±6.4 kg/m 2 ). Children with MASLD lived in neighborhoods with significantly lower HPI scores than those without MASLD (−0.22 vs. −0.03; 41st vs. 49th percentile, p =0.01). They also resided in areas with significantly lower socioeconomic advantage across multiple HPI subdomains, including housing (−0.16 vs. 0.03; 44th vs. 51st percentile, p <0.001) and economic (−0.38 vs. −0.12; 36th vs. 55th percentile, p <0.001) scores. Conclusions: Children with MASLD were more likely to live in neighborhoods with greater socioeconomic and environmental disadvantage than their peers with overweight or obesity but without MASLD. These findings highlight potential SDH targets for public health interventions aimed at reducing MASLD risk in children.