The present invention provides a prophylactic and/or therapeutic agent for non-alcoholic fatty liver disease (NAFLD), and particularly non-alcoholic steatohepatitis (NASH) comprising an ume (Japanese apricot) juice concentrate or a processed product thereof. The prophylactic and/or therapeutic agent is obtained by utilizing a component contained in a plant or a processed product thereof, and hence is safe and easily taken. It has been confirmed that when the ume juice concentrate or the processed product thereof is orally administered to a streptozocin (STZ)-induced NAFLD model mouse or an STZ-induced NASH model mouse, liver fibrogenesis can be reduced.
