Although quality orientation is one of the main priorities of any progressive organization, quality evaluation in organizations providing services such as hospitals is one of the key challenges, because in this sector quality is determined by many intangible factors. Applying the service quality gap model is one of the common tools for quality evaluation in the service sector. This paper seeks to evaluate this issue. The present descriptive study was carried out through a cross-sectional method in 2008. The participants of this study were patients who had been referred to Kerman University of Medical Sciences hospitals. The sample comprised 385 patients, the data were collected by SERVQUAL as a standard questionnaire, and data analysis was carried out on 385 completed questionnaires. In all five dimensions of quality, a gap was observed between patients' perceptions and expectations as follows: Assurance: -1.28, Empathy: -1.36, Responsiveness: -1.80, Tangibles: -1.86 and Reliability: -1.69. A paired T-test showed that the differences between quality perceptions and expectations are significant (p value < 0.05). Based on the findings of this research, the hospitals in the study did not meet the expectations of patients and were unable to provide health care services according to patients' expectations. Hence rearranging the service delivery and deploying better facilities and equipment in order to decrease the gap between patients' perceptions and expectations may be helpful. The paper reports an original application of the SERVQUAL approach to hospital services of a developing country.