Juvenile idiopathic arthritis (JIA) is the most common condition of chronic rheumatic disease in children. JIA is an autoimmune or autoinflammatory disease, with unclear mechanism and limited treatment efficacy. Recent studies have found a number of alterations in gut microbiota and its metabolites in children with JIA, which are related to the development and progression of JIA. This review focuses on the influence of the gut microbiota and its metabolites on immune function and the intestinal mucosal barrier and discuss the key role of the gut-joint axis in the pathogenesis of JIA and emerging treatment methods based on gut microbiota and its metabolites. This review could help elucidate the pathogenesis of JIA and identify the potential therapeutic targets for the prevention and treatment of JIA.