The invention belongs to the technical field of steering engines, and particularly relates to a constant linear load simulation device. The linear load simulation device comprises a cover plate, a screw rod rotating base, a screw rod rotating pin, a baseplate, a first locating block, a limiting block, a steering rod locating pin, a steering rod, a spring fixator, a spring, a nut, a screw rod and a tacking nut. The problem in the prior art that there is no linear force loading equipment which can be used for testing the accuracy and the degree of stability of the steering engine action in a simulation way can be solved. The characteristics that the elongation of the spiral spring is in direct proportion to the size of the tensile force, and the linear force output is stable and high in reliability are utilized, the elongation of the spring is fixed through thread self-locking, and direction change of the linear force can be guaranteed through combination of multiple single-degree-of-freedom joints so as to have force output of forward and backward directions, the linear simulation load of forward and backward directions can be provided for the linear steering engine, and testing of the accuracy and the degree of stability of the steering engine action can be met.