Background: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of pediatric liver disease. Its prevalence is related to the growing epidemic in childhood obesity during the past decades. At present, NAFLD and nonalcoholic steatohepatitis (NASH) are increasingly recognized worldwide. In spite of alarming trend in the epidemiology in pediatric field and growing risk of end stage liver disease, there is no significant advance in its diagnosis and treatment. Aim: To provide a detailed review for diagnosis and management of NAFLD and NASH. Methods: By using Pubmed to find review articles and relevant research. Results: The prevalence ranges from at least 3% in children overall to about 50% in obese children. The noninvasive biomarkers can be used to identify NAFLD/NASH patients. Diagnostic criteria based on biochemical and immunological indicators in the high-risk group of children could prevent about half of cases from receiving an invasive test. The pharmacological and surgical interventions have shown a growing role in pediatric NAFLD. Novel treatment modalities, such as probiotics, have hardly been studied. Conclusion: Early diagnosis by using noninvasive screening methods in high-risk groups is the most effective strategy against the NAFLD. The biology of early growth and development, including hepatic metabolism, may hold the key to pediatric NAFLD. Prevention of overweight children and childhood obesity is undoubtedly the best strategy for treating NAFLD.