Purpose: The study aimed to extract the space mentioned in the criteria for evaluation and certification of psychiatric institutions in which the most specific standards for medical services of psychiatric institutions are prepared, and to organize and analyze the requirements. Method: The implied space is derived by analyzing the evaluation and certification criteria. The derived space is re-classified by departments of the hospital, and the requirements are organized and analyzed. Results: First, a total of 41 spaces were derived. The derived spaces can be considered as spaces to be treated as important in psychiatric institutions. Second, as a result of reclassifying the derived space by department, 10 spaced for the hospital as a whole, 10 for wards, 12 for central/outpatient departments, 5 for pharmaceutical departments, 2 for catering facilities, and 2 for facilities. Third, if organized by psychiatric institution, there is a total of 40 spaces for psychiatric hospitals according to certification criteria, and according to evaluation criteria, there is 38 spaces for psychiatric hospitals and departments and 19 spaces for the clinics. The difference between the certification and evaluation criteria of psychiatric hospitals is insignificant. In order to promote the qualitative improvement of psychiatric institutions, it is necessary to gradually strengthen from the certification criteria. Fourth, the requirements reflecting the characteristics of a psychiatric institution were very limited to emergency exits and treatment rooms. It is necessary to prepare the space requirements for other rooms in consideration of the behavior of the mentally ill. Implications: The derived spaces and requirements can serve as practical reference materials for practitioners preparing to receive certification and evaluation of psychiatric institutions. In addition, it has meaning as a basic data for estimating the level of space and requirements of psychiatric institutions that are currently required in Korea.