The utility model relates to an asphalt mixture fatigue test device. A base is arranged at the bottom part inside a constant temperature box; a left bracket is arranged on the left side of the base, a right bracket is arranged on the right side of the base, one end of a transverse rod provided with a hydraulic oil cylinder is arranged on the left bracket, and the other end of the transverse rod is arranged on the right bracket; a vertical force sensor is arranged at the end part of a piston rod of the hydraulic oil cylinder, a wheel fork provided with an idler wheel is arranged at the lower end of the vertical force sensor and provided with an output shaft and a stepping motor which is connected with the idler wheel, and a computer, a programmable controller and an electromagnetic valve are arranged outside the constant temperature box; an elastic sponge is arranged on the base, and is provided with an elastic thin plate on which an asphalt mixture specimen is arranged, a strain sensor is arranged on the asphalt mixture specimen, the idler wheel contacts the upper surface of the asphalt mixture specimen, and the strain sensor is connected with the computer through a conducting wire. The programmable controller is connected with the computer and the electromagnetic valve through the conducting wire, and the electromagnetic valve is communicated with the hydraulic oil cylinder through a guide pipe.