This paper is concerned with the optimal design of hyperbaric oxygen therapy system chamber with separated rooms for multi-users using stress analysis. Hyperbaric oxygen therapy is very important medical remedy for increasing the concentration of melted oxygen in human and animal body to recover the impaired cell for the healthy condition. This research proposed the proper procedures to design the physical specifications and investigate the mechanical design safety of hyperbaric oxygen chamber with two separated rooms using computational stress analysis with Solidworks program. The result of this research will be used to make the real size model of practical hyperbaric oxygen therapy system for multi-users with separated chamber.