This paper examines whether there is a significant difference between Peruvian private health companies that have a Quality Management System (QMS), in comparison to those that do not have one, based on the nine key success factors for Total Quality Management (TQM) implementation and the relation with the ISO 9000:2015 principles on each factor. The methodology used to measure TQM is based on an instrument of four (4) blocks (top management, supplier, process and customer) with nine (9) success factors and thirty-five (35) variables. We analyzed the responses of the surveys sent to 120 private health companies and found that certified companies have significant differences and a better average in eight of the nine success factors in all the TQM blocks.