Background: The use of Cooperative Institutional Review Board (Co-IRB) has become subject to continuous discussion. As a result, leading mainly by the Korea Association of Institutional Review Boards (KAIRB), "IRB mutual recognition program (MR-IRB)" was proposed. However operational methods of the program are still controversial. The object of this research is to examine domestically feasible scope and operation methods of MR-IRB by conducting survey. Methods: 71 survey data was collected from chairman or specialist of each IRB and 29 IRB members of one institution running Central IRB was included. Results: 76.5 % of respondents selected phase 3 multi-national, multi-center clinical Sponsor Initiated Trial as a suitable subject of MR-IRB, but only 50 % supported Investigator initiated trials, and answered early-stage clinical trials such as phase 1 clinical trials or biological agent trials are unsuitable due to relatively insufficient knowledge on risk level. In order to operate MR-IRB, standardized review criteria and agreement of institutions in building mutual trust is essential. Also it was learned from the survey that the most desirable way to adopt MR-IRB is to be initiated by the representing organization such as KAIRB based on mutual trust from institutional agreement. Conclusion: MR-IRB was recognized as one of Co-IRB. A suitable subjects of MR-IRB were preferred the phase 3 multi-national, multi-center clinical sponsor initiated trials to all kinds of clinical trials. This study suggests that based on real operation experience from MR-IRB pilot study, further study should be conducted to analyze pros and cons of MR-IRB and identify domestically eligible model to facilitate MR-IRB.