Inflammation is involved in the development and progression of nonalcoholic fatty liver disease (NAFLD). The monocyte to high-density lipoprotein cholesterol ratio (MHR) has emerged as a marker for various inflammation-related diseases. The aim of the present study was to investigate the association between the MHR and NAFLD in a population with childhood obesity. Based on hepatic ultrasound, a total of 504 children with obesity (357 with NAFLD and 147 without NAFLD) were included in the study. The correlation between the MHR and NAFLD risk factors was assessed by Pearson's and Spearman's analyses. Multivariate stepwise logistic regression analyses were conducted to explore the association between the MHR and the risk of NAFLD. The MHR in patients with NAFLD was significantly greater than that in patients without NAFLD [0.52 (0.44-0.67) versus 0.44 (0.34-0.57), P<0.001]. Multivariate stepwise logistic regression analysis demonstrated that the MHR [odds ratio (OR): 1.033, 95% confidence interval (CI): 1.015-1.051; P<0.001] was an independent predictor of NAFLD in childhood obesity patients, as were age (OR: 1.205, 95% CI: 1.059-1.371; P=0.005], waist circumference [OR: 1.037, 95% CI: 1.008-1.067; P=0.012], and alanine transaminase [OR: 1.067, 95% CI: 1.045-1.089; P<0.001]. Additionally, MHR quartiles showed a significant positive association with the incidence of NAFLD after adjusting for potential confounding factors. The present study showed that the MHR may serve as an available and useful indicator of NAFLD in individuals with childhood obesity.