Background Childhood obesity is a global problem associated with metabolic abnormalities. The gut-liver axis is thought to play a major role in its pathogenesis. Probiotics are known to alter the gut microbiota and, therefore, could be a therapeutic option in the management of childhood obesity-related complications.Purpose This double-blind randomized placebo-controlled trial evaluated the effects of probiotics on metabolic derangement in obese children with nonalcoholic fatty liver disease/nonalcoholic steatohepatitis (NAFLD/NASH).Methods Obese children with NAFLD/NASH treated at the nutrition clinic of the University Paediatric Unit at Lady Ridgeway Hospital, Colombo, were recruited. Anthropometry, body fat, metabolic derangement, and liver ultrasound scan (USS) results were evaluated at baseline and after 6 months. Transient elastography (FibroScan) was performed on a subsample of these patients. Eighty-four patients were recruited and randomized into the probiotics (n=43) and placebo (n= 41) groups. The mean age was 11.3±1.9 versus 12.1±1.5 years in the probiotic and placebo groups, respectively. Baseline parameters including liver disease stage on USS, body fat percentage, fasting blood sugar, lipid profile, liver function, and C-reactive protein showed no significant intergroup differences.Results In the probiotic group, a statistically significant reduction in body mass index was noted from the baseline value. However, the reduction was not significant compared with the placebo group. There was a significant reduction in triglycerides, aspartate transaminase (AST), alanine aminotransferase (ALT), AST/ALT ratio, and alkaline phosphatase in the placebo group over the treatment period. Although the liver disease stage on USS improved from stage II–III to stage I in a small number of patients in the probiotic-treated group, transient elastography performed in a subsample did not demonstrate significant improvement in either group.Conclusion Our results indicate that probiotics have no advantage over lifestyle modification for improving obesityassociated metabolic derangement in children.