The work aims to improve the filling precision of the filling equipment and solve the splashing problem in the filling process. According to the structural features of existing valve, a central-small-flow filling valve was creatively designed which was opened with the valve stem moving up. In the filling valve, a cone sealing was formed between the lower conical surface of piston head and the piston sealing plate, thus leading to an inner sealing structure at high position of the plunger plug. The small-flow channel composed of transverse diversion hole and the central diversion hole was designed on the piston head. The filling valve was at a stable small flow velocity, the filling precision was easily controlled and no splashing phenomenon occurred during working, which was not only suitable for the packaging of ordinary liquid materials, but also could be used in the filling equipment for paste material with high viscosity. A large number of practices show that the filling valve is featured by many advantages, such as reasonable structure, high reliability and wide application range, and it has good promotional values and economic benefits.