The purpose of this study is to clarify architectural feature of o-chaya in Fukuoka domain. This study is based on Utino, Akama, Yamae's drawings. This study gives attention to the outer building and the inner building and design. As a result, site plan and building plan have many points in common. Three o-chaya divide into four parts in terms of space and design. O-genkan part is traffic place whose design is syoin. O-hiroma part is meeting place whose design is informal syoin. O-ima part is resting place whose design is like sukiya. Tumesyo-daidokoro part is cooking and administration place whose design is like minka.