The invention discloses an Under-floor Lifting Jack for High-Speed EMU trainset, comprising: a Main Electric Control Part for controlling the Jack, multiple Bogie Lifting Means arranged in pits, Fixed Rails on the ground between adjacent pits, and Body Hoists movable along dedicated rails on both sides of the Bogie Lifting Means, wherein Lifting Rails of the Bogie Lifting Means and the Fixed Rails form continuous rails, and one or more of the Bogie Lifting Means are set in each pit and adapted for lifting individually or synchronously in combination according to the wheel positions of different types of Electric Multiple Unit Trainsets wider the control of the Main Electric Control Part. The invention is compatible with the maintenance of various EMU trainsets, thus the same lifting jack can satisfy maintenance requirements of various EMU trainsets, resulting in high compatibility and construction cost-reduction of the maintenance base for the EMU trainset.