Proportional type pressure reducing valve consists of valve body, piston, gland, O-ring, seal pad etc. The valve is set with a floating piston in its internal cavity and changes the pressure at water inlet and outlet by means of the pressure difference caused by different horizontal areas on both sides of the piston .The area difference on both sides of the piston in the pipeline subjected to pressure makes the pressure difference on both inlet and outlet of the valve, thus get the purpose of pressure reduction. This valve can reduce both" dynamic" and "static" pressure, having a strict and brand-new structure, smooth movement, exquisite volume, light weight. And it is easy to be mounted and maintained, wearable and leak-preventing. It is made by using the advanced workmanship and surface treatment; therefore it is corrosion-proof and rust-proof without pollution to water nature.