With regard to EC50 values (mg extract/ml) of methanolic extracts, inhibitions of peroxidation were excellent and in the descending order of PR>DR>MDR>MPR. Effectiveness in reducing powers was in the descending order of MPR⪢MDR⪢DR>PR. Scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl radicals were in the descending order of MPR>MDR>PR∼DR. Chelating abilities on ferrous ions were in the descending order of MPR∼MDR>PR>DR. Total phenols were the major naturally occurring antioxidant components found. Overall, monascal rice products were better in reducing power, scavenging and chelating abilities and higher in total phenol content than uninoculated rice products.