This step measuring device and measuring method are disclosed. Step number measuring apparatus according to the present invention, the geomagnetic detection unit according to the body movement by using a geomagnetic sensor for outputting each axis digital value, each axis the N digital values ​​of each axis the (N-1) digital values, and each axis the (N-2) and a reference digital value generator for generating the each axis reference digital value based on the digital value, the search for an axis the N digital value having the maximum amplitude, and the reference axis selection to select an axis as the reference axis portion and, as a digital value size determining unit for determining whether the reference axis N th the size of the digital value is greater than a predetermined value than the size of the reference axis based on the digital values, a larger case, ascending movement of one footstep the body movement greater than a predetermined value and a control unit for determining. Thereby, the power consumed in the step number measuring apparatus can be reduced. Step measuring device, the reference digital value, the reference axis