An adjustment and calibration method and system for electric motor overload protection. The adjustment and calibration method comprises the following steps: collecting a working current of an electric motor in real time (S110); determining whether a current difference value between the working current of the electric motor at each time and the corresponding initial protection current satisfies a pre-set requirement (S120); and if it is determined that the current difference value does not satisfy the pre-set requirement, adjusting same to be an initial protection current satisfying the pre-set requirement, so as to set the initial protection current (S130). The adjustment and calibration method realizes automatic adjustment and calibration of a protection current, and can thus perform accurate overload protection on an electric motor according to the adjusted and calibrated protection current, thereby reducing the situations where electric motor damage occurs caused by an overload, and improving the working e
