The embodiment of the invention provides an acquisition method of the load displacement of a motor. The acquisition method comprises the following steps of: selecting a fixed time interval t; acquiring k operating parameters of the motor at the time interval t, wherein the k is a positive integer more than 1; and obtaining the load displacement S of a load driven by the motor according to the k operating parameters of the motor at the time interval t. According to the invention, the load displacement S of the load driven by the motor can be obtained by adopting industrial control equipment and a frequency converter on an industrial field without needing to utilize an additional load displacement detecting device, so that the problems that the load displacement detecting device is easily interfered by the environment and the frequency of faults occurring on the detecting device is higher to cause the lower accuracy of the acquired load displacement of the motor in the prior art are solved. In addition, the embodiment of the invention also provides an acquisition device of the load displacement of the motor.