The invention discloses a high-speed train power closed loop hanging-type gearbox reliability test bench, so as to overcome the problem that a reliability test can not be carried out on the actually-operating train gearbox. The high-speed train power closed loop hanging-type gearbox reliability test bench comprises a rectangular bearing platform, a gantry vertical excitation device, a vertical hanging device, a vibration shaft device, a transverse excitation device and a motor torque force measurement device, wherein the gantry vertical excitation device is arranged at the rear end of the rectangular bearing platform; the vertical hanging device is arranged at the top end of the gantry vertical excitation device; the vibration shaft device is arranged in a first U-shaped groove and a second U-shaped groove of the vertical hanging device; the transverse excitation device is arranged in front of the gantry vertical excitation device; a two-force rod fork of the transverse excitation device is in rotary connection with a first shaft head assembly in the vibration shaft device; first counterforce supporting seats in four counterforce seat assemblies of the motor torque force measurement device are symmetrically arranged at the left side of the first U-shaped groove and the right side of the second U-shaped groove; and four force measurement sensors are in bolt connection with the first U-shaped groove and the second U-shaped groove.