Background and Aim: Assessment of clinical skills has a central role in dental education. OSCE has been introduced as an effective method to provide a reliable assessment in this regard. This study aimed to describe postgraduate dental students' perceptions toward the annual OSCE carried out in an Iranian dental school.Materials & Methods: All postgraduate dental students were asked to participate in this descriptive cross-sectional study. Two questionnaires (pre-test and post-test) were designed and were distributed before and after the OSCE respectively. Data were retrieved and subjected to analysis via SPSS 16. Results: The overall attitude of dental residents towards OSCE was positive, however, there were significant differences between pre-test and post-test results among different departments (P<0.05). Nearly half of the examinees were in favor of written questions included in OSCE (44.4%). Substantial proportion of them found OSCE as a stressful method. Conclusion: A non standard and stressful mode of OSCE may affect the examinee's attitude toward this method, hence, it is strongly recommended that considering the importance and success of OSCE, examiners improve the standards and setting of this means of evaluation.