It is a high-frequency aluminum electrolytic capacitor specially used for switching regulated power supply. It has four terminals. The current of the regulated power supply flows from one positive end of the four-terminal capacitor, passes through the inside of the capacitor, and then flows from the other positive end to the load; the current returning from the load also flows from one negative end of the capacitor, and then flows from the other negative end to the power supply negative terminal. Because the four-terminal capacitor has good high-frequency characteristics, it provides an extremely advantageous means for reducing the pulsating component of the output voltage and suppressing the switching peak noise.