The invention relates to an adjustable orifice plate device which comprises an orifice flange, an orifice-free flange, an orifice plate, a gasket, a bolt and a nut, wherein the orifice flange is internally provided with a throttle baffle plate, a first flow through hole is formed on a plane on which the throttle baffle plate is arranged, the outer wall with the orifice flange is convexly providedwith a first flange along the radial direction, and a first through hole which axially runs through is arranged on the first flange; the outer wall of the orifice-free flange is convexly provided with a second flange along the radial direction, and the second flange is provided with a second through hole which axially runs through; the orifice plate is assembled between the orifice flange and theorifice-free flange, and a second flow through hole is arranged in the orifice plate; the gasket is arranged at two sides of the orifice plate and between the orifice flange and the orifice-free flange; and the bolt passes through the corresponding first through hole and the corresponding second through hole and is matched with the nut to enable the orifice flange to be fixedly connected with theorifice-free flange. By the invention, the flowing area can be changed according to the practical demands so that the adjustable orifice plate device can adapt to different fluid flowing requirements.