Purpose: The standardized patient (SP) is a person carefully trained to represent a real patient case for consistent and accurate use in student performance evaluation and/or training, has added a very important dimension in OSCE. The purpose of this study is compared a well-trained professional SP (PSP) and a amateur SP (ASP) in OSCE. Methods: We surveyed 378 students apprentices and staffs involving OSCE of Daegu-Kyungbuk Consortium and analysed the validity between the PSP and ASP after OSCE. Results: Of 92 total stations in which students were evaluated by staff evaluator, SP were used in 47 stations (48%). Of the 47 stations, professional SP 7 stations (16%). The questionnaires were made to know the effectiveness and realistics of SP. The results were different between station used PSP and ASP. Moreover, it was significantly different between the staffs and the students. The SP can offer advantages such as availability, adaptability and effectivity. If trained well, they also can provide positive effects to the students and the staffs. The PSP provides efficient and reliable opportunity to assess clinical skills in a safe situation without any harm to the real patients. Conclusion: It is suggested that the use of SP is stimulating and challenging way of evaluating the OSCE. Also, It appeared to be financially and availably feasible if it commonly owned in the boundary of the land such Daegu-Kyungbuk Consortium.