Large energy-storage high-vacuum holding pump

The utility model relates to the field of hydraulic machines, in particular to a large energy-storage high-vacuum holding pump. The large energy-storage high-vacuum holding pump comprises at least one holding unit comprising a first cylinder, a first piston, a first piston rod and a first hydraulic cylinder. The first hydraulic cylinder is connected with one end of the first piston rod and is used for driving the first piston rod to move in the axial direction of the first piston rod in a reciprocating mode, the first piston rod is connected with the first piston, the first piston is arranged in the first cylinder and divides the first cylinder into an upper cavity and a lower cavity, the upper cavity is provided with an air inlet valve communicated with the outside, and the lower cavity is provided with an exhaust valve communicated with the outside. After the holding pump takes the place of a whole main pumping unit, operation is easy, cost and energy consumption are low, maintenance is easy, polluting gas is not emitted, and environment protection is achieved.