Due to the pursuit of high power-to-weight ratio, the pressure and flow margin of the civil aircraft hydraulic energy system is small. However, due to the large number of users and the complexity of the system, if the pressure flow margin is too small, flow pressure disputes may occur under some flight profiles, so the system pressure is not reachable. Therefore, the pressure accessibility analysis is the primary task of the civil aircraft hydraulic energy system design. Taking a set of hydraulic energy system of the civil aircraft 34.47 MPa（5 000 psi）pressure system 2H/2E energy system architecture as the object, based on the analysis of its working principle and pressure loss mechanism, the standard model and super model of related components were built in AMESim software, then the simulation analysis model of the hydraulic energy system was built to obtain the pressure accessibility law of the aircraft hydraulic energy system at an ambient temperature of -8 ℃. At present, the 2H/2E energy system architecture and hydraulic system research of the domestic civil aircraft 34.47 MPa（5 000 psi） pressure system is in its infancy. The relevant research results will provide support for the development of wide-body aircraft, at the same time, it provides reference for the design, evaluation and optimization of the hydraulic energy system of large civil aircraft in China.