The invention discloses a power capacitor with less process. The power capacitor comprises a capacitor shell, a seal ring and a binding post fixed on the capacitor shell, wherein the binding post comprises a ceramic insulator, and an annular locating boss is arranged on the lower outer wall of the ceramic insulator; the capacitor shell is provided with an installation sleeve; the installation sleeve comprises a pressing part, a sleeving part and a rolling loop part, wherein the pressing part is used for pressing the seal ring on the bottom wall of the locating boss, the sleeving part is sleeved on the peripheral wall of the annular locating boss and the rolling loop part is buckled on the annular locating boss through a rolling way; the pressing part is formed by the wall of a rolling tube, wherein the pressing part is in an annular boss shape inside the tube, of which the section is either in a V shape or a U shape, and the pressing part outside the tube is an annular groove shape, of which the section is either in a V shape or a U shape. The sleeve is buckled on the lower part of the insulator by rolling and buckling to fixedly install the binding post on the capacitor shell. The power capacitor provided by the invention has the advantages of less process and lower cost.