Method and apparatus for evaluating quality of a product, and a recording medium therefor. The invention includes creating and storing in advance a workshop evaluating database, extracting from the prepared workshop evaluating database those failure occurrence ratio indexes which correspond to workshop facility levels of an input manufacturing workshop for workshop-conditioned failure influential items thereof, respectively, and evaluating/estimating failure occurrence likelihood for standard manufacturing works in the manufacturing workshop, the failure occurrence likelihood being then stored as workshop index in a product evaluating database, and evaluating/estimating a quality indicating a work-related defective ratio for the products to be manufactured through a plurality of manufacturing works in the manufacturing workshop by using the workshop indexes concerning that manufacturing workshop which has been stored in the article evaluating database in the workshop evaluating step.