Abstract: A portable terminal (1) includes: an X-axis direction body movement sensor (11), a Y-axis direction body movement sensor (12), and a Z-axis direction body movement sensor (13) for detecting accelerations in a plurality of directions; a scalarizing section (103) for combining the accelerations detected by the X-axis direction body movement sensor (11), the Y-axis direction body movement sensor (12), and the Z-axis direction body movement sensor (13), so as to obtain a combined value, and then scalarizing the combined value; a peak value detecting section (105) for obtaining, at every given time, the combined value obtained by the scalarizing section (103), and detecting an upper peak value and a lower peak value of the combined value thus obtained; and a step counting section (106) for counting another step when a difference between the upper peak value and the lower peak value which have been detected by the peak value detecting section (105) exceeds a given value.