The ZZYP-II pilot-operated self-acting pressure regulating valve requires no external energy and uses the energy of the controlled medium for automatic regulation. It employs a single-seat quick-opening regulating mechanism and provides stable medium pressure, high regulating accuracy, safe and reliable sealing, and adjustable setpoint during operation. It is suitable for micro-pressure automatic regulation of fuel gas in industrial furnace combustion systems, protective gases such as nitrogen blanketing for petroleum products and storage tanks, and protective gases used in heat treatment.