This study aims at applying cold-formed square hollow section members to high rise building for high rise steel structure system adaptable to Korean circumstance in the point of load capacity and construction availablity by beam- to-column connection composed of H-section beam and cold-formed square hollow section column. Based on this investigation of the test result, we are to acquire report, detail design of beam-to-column connection according to new beam-to-column connection system used cold-formed square hollow section members.