In Japan which has the most number of psychiatric beds among the developed countries, finding out the form for Japanese psychiatric health care which aims to improve the quality of life for patients while maintaining the form of a psychiatric hospital, is an urgent task.With the opinion that matching the diversifying needs of patients, and building Psychiatric hospitals to ensure life with the grade and quality equal to life in the communities, is one way to go forward for Psychiatric health care in our country, this study aims to explore the form for psychiatric hospitals from the perspective of architectural planning.The survey targeted a total of 5 wards in Fukushima Prefecture with a focus on Hospital A Building A 4-bed rooms (Acute period ward, Convalescent ward, Stress care ward). and Building D with all private rooms (Super emergency ward, Stress care ward). Spaces are organized into Private space, Semi-private space, Semi-public space, Public space, by stages , And a spatial feature of the surveyed targets, is that the ward is shaped in a cluster surrounding the S-pri. The summary is showed below.1. Shared space utilization, was high for Multi-bed rooms, and wards with many schizophrenia patients, and lowered with the lessening of symptoms and longer hospital stays.2. Usage characteristics of shared space and behaviors are influenced by the disorder. A tendency was seen for Schizophrenia patients preferring to stay in the S-pub.space, and Stress disorder patients preferring to stay in the S-pri.space.3. Regarding interactions with others, as seen through the manner of stays, the differences in behavioral traits by disorder, maintaining of distance with others, showed the differences in spatial needs. At that time, the element that has decisive influence is the spatial composition. For multi-bed room wards, the percentage of there alone; for all private room wards the percentage of gathering; and in wards with many acute phase schizophrenia patients, the percentage of there with others was large. For all private room wards, there were many patients who used the Chat corner as there with others space.