It is considered several quality management systems (QMS) peculiar to the information technology (IT) to manage IT processes systematically. There are a lot of expected effects and benefits from these systems in the literature. In this study, these expected benefits were grouped according to literature research as increasing in product and service quality, increasing in the satisfaction and loyalty of customers, increasing in project management performance, increasing in the team management and motivation, financial benefits, managerial benefits. After that, it was tried to figure out whether or not the mentioned benefits are made by comparing the firms which were classified into three groups. First group firms have quality management systems peculiar to the information technology. Second group firms use general purpose quality management systems, and last group firms don‘t apply any of these quality systems. As a result of surveys and analyses, such differences were observed in some expected effects.