This work aims to assess possibility to setup relaxation space on mostfrequent used by seafarer for resting and relaxing. The focus is addressed on the sleeping accommodation and mess room, with three approaches to setup such space are considered by reviewing coloring, lighting and flooring. To conduct the assessment, fundamental literature of fatigue phenomenon is presented based on pioneer works in shipping activity. After solid background and necessity are clarified, the design requirement of merchant ship for crew accommodation is reviewed to ensure the design planning for relaxation space is also satisfy classification standard. Several forms of relaxation space's concept based on different approaches are presented in discussion. Finally, from three approaches, it is concluded that coloring is the suitable in setting-up a relaxation room, especially in sleeping accommodation. Further design on the mess room requires collaboration of three approaches to reach good comfortableness level.