YD43H pilot type super large diaphragm high sensitivity pressure reducing valve is a new type of pilot type super large diaphragm pressure reducing valve successfully developed by the company with reference to foreign advanced products, YD43H pilot type super large diaphragm high sensitivity pressure reducing valve has made great improvements on the basis of ordinary pressure reducing valves. The diaphragm adopts a new material and greatly processes the working area, so that the slight changes in the upstream pressure or downstream load of the valve can be fed back to the main valve diaphragm in time and accurately to adjust the opening of the main valve and ensure the stability of the downstream pressure. Another outstanding feature of YD43H pilot operated ultra-large diaphragm high sensitivity pressure reducing valve is that multiple pilot valves can be installed and exchanged on the same valve body to achieve temperature control, upstream pressure control, remote switch control, etc. while stabilizing pressure.