The invention provides a pressure regulator. The pressure regulator is mainly used for solving the problems that in an existing pressure regulator, the outlet pressure rated point regulation precision is low, the outlet pressure regulation range is wide, and the product structure size is large. The pressure regulator comprises a regulator body with an inlet and an outlet and a filler neck arranged at the upper end of the regulator body. A valve assembly is arranged in an inner cavity of the filler neck and comprises a valve element and an auxiliary spring, and the auxiliary spring is mounted in the valve element. A metal membrane, a tray and a spring seat are sequentially arranged at the lower end of the regulator body from top to bottom in an attached manner. An ejector rod is arranged between the valve element and the metal membrane. The ejector rod and the metal membrane selectively form a sealing cavity in the inner cavity of the regulator body. The pressure regulator is characterized in that the spring seat is provided with a guide segment; a cylindrical spring is arranged on the inner side of the guide segment; a fine regulation nut is arranged at the lower end of the cylindrical spring; the cylindrical spring is pressed by the fine regulation nut; a belleville spring is arranged on the outer side of the guide segment; a rough regulation nut is arranged at the lower end of the belleville spring; and the belleville spring is pressed by the rough regulation nut.