The objective of the H-II Orbiting Plane-Experimental(HOPE-X) project is to develop the major technologies necessary for two-way space transportation systems on the bases of precursor elemental flight experiments such as OREX, HYFLEX and ALFLEX and to demonstrate them through the flight experiment of an operational size vehicle. At present, the HOPE-X project is in the development phase and various efforts for system design and fundamental technologies are being conducted through the co-operational works between the National Aerospace Laboratory (NAL) and the National Space Development Agency of Japan (NASDA). Moreover the plan to improve the HOPE-X vehicle after the flight experiment and to use it for practical missions is investigated.