The invention provides a capacitor for 750kV reactor partial discharge test device. The capacitor includes a shell, a core and an outgoing line sleeve, and a joint hinge is arranged on the shell; the core includes an element and an insulating part, the shell includes an upper section, a middle section and a lower section, and silicone rubber umbrella skirts are arranged on the upper section and the lower section; the element includes a first electrode layer and a second electrode layer which are oppositely arranged in parallel, and a third electrode layer and a fourth electrode layer arranged between the first electrode layer and the second electrode layer, and the third electrode layer and the fourth electrode layer are separated from each other through the insulating part and are of wave-shaped bending structures. When the capacitor is used in a high-altitude area, the phenomena of creepage, discharge and breakdown do not occur, and the safety is high; through structural design of the element, the capacity of the capacitor is greatly increased while the volume of the shell is not increased; and the capacitor has high pollution flashover resistance, has the advantages of having good processing performance, being not easy to deform, and having high dielectric strength, and is suitable for use in a high-altitude high-voltage area.