Hospitals are increasingly realizing the need to focus on service quality as a measure to improve their competitive position in today's highly competitive environment. The aim of the study is to evaluate the service quality of hospitals from the customers' perspective and comparing public and private hospitals. In this study, a total of 610 customers were selected randomly and asked to complete a questionnaire that was designed according to SERVQUAL methods. This questionnaire measured customers' perceptions and expectations in five dimensions of service quality that consists of tangibles, reliability, responsiveness, assurance and empathy. The quality gap of hospital services was determined based on differences between customers' perceptions and expectations. In general, the evaluation of the service quality of the hospitals that the customers preferred are negative (SERVQUAL Score = -0,328). When we examine the hospitals' SERVQUAL scores according to their type of property, public hospitals (SERVQUAL score = -0,394) are negatively evaluated by consumers in comparison to private sector hospitals (SERVQUAL score = -0,246). The results of this research suggest that the SERVQUAL instrument is a useful measurement tool in assessing and monitoring service quality in hospitals, enabling the staff to identify where service improvements are needed from the customers' perspectives.