The Sino-Russian Joint Mars-Phobos Exploration program provides unique opportunity to investigate the global structure of the solar wind/Mars interaction region. The Mars orbiter YH-1 will carry a plasma package consisting of two identical ion detectors, and one electron detector, which is aimed at monitoring the plasma with energy up to a few keV in the environment of the planet, provides a mass analysis of the ions in the mass range form 1 to 44 au. Together with the magnetic field experiment on board YH-1, the plasma package will be the first to give full insight into the local plasma characteristics near the planet, as well as to determine the possible the total ion escape (particles/s) for the major ion species.