Exhaust nozzle research was conducted to develop design technologies for propulsion system of Hypersonic transport. According to engine cycle study, nozzle cross sectional area should be variable for nozzle pressure ratio up to 270 level. Trust coefficient should be 0.95 to meet 2.0kg/hr/kg of SFC at Mach 5. And nozzle liner have to endure 1900C level gas temperature. So exhaust nozzle to have two dimensional (2-D) variable geometry and cooling structure. Aerodynamic study was conducted by model test and CFD. As result, target thrust coefficient was achieved. Variable geometry mechanism is designed to have convergent/divergent flaps and side walls. Convergent/divergent flaps are separated to introduce ambient air from throat into inside of nozzle at take-off. Integrated film and impingement cooling structure is designed using composite for liner based on heat transfer coefficient distribution and cooling efficiency, acquired by model test. This paper describes 2-D Variable Exhaust Nozzle Research.