Aluminum casing for electrolytic capacitor

The invention provides an aluminum casing for an electrolytic capacitor. The aluminum casing comprises an aluminum casing body (2), wherein an insulating film (1) is arranged on the inner wall of the aluminum casing body. In the electrolytic capacitor, the insulating film is arranged on the inner wall of the aluminum casing, and the inner wall of the aluminum casing body can be prevented from directly contacting a cathode and an anode in a capacitor core by utilizing the film, so that the capacitor is prevented from short-circuiting. Therefore, the capacitor core in the electrolytic capacitor can be extended to ensure that the capacitance is increased by 40 percent under conditions of invariable outer diameter of the aluminum casing and the same pressure resistance.