The adjustable shock absorber bottom valve is a valve that controls how much oil is allowed to flow from the tank to the working cylinder. The oil flow is controlled by the piston valve, which moves up and down with the piston rod. The valve regulates the amount of fluid discharged from the piston rod to expand the air cushion. The piston valve enables the shock absorber to respond to the forces generated by vehicle vibration. The bottom valve of the shock absorber is fixed at the bottom end of the inner cylinder barrel, and the bottom valve is provided with a plurality of oil leakage holes that penetrate the bottom valve body along the axial direction. When the automobile shock absorber is working, when the piston in the inner cylinder barrel of the working cylinder moves up and down, the oil flows repeatedly between the inner cylinder barrel and the working cylinder, and the flowing oil flows through the oil leakage hole of the bottom valve and rubs against the wall of the oil leakage hole, which will produce damping force to attenuate vibration. The adjustable shock absorber bottom valve is a very important part of the suspension system. It can reduce the noise caused by vibration. In addition to shock absorption, it can also reduce energy consumption.