The present invention provides a step counting method and device. The method comprises the following steps performed repeatedly: a) obtaining three monoaxial acceleration signals with a predetermined length from triaxial output of a triaxial acceleration sensor worn on a walkrunner b) performing high-pass filtering on each obtained monoaxial acceleration signal c) performing pitch detection on each high-pass filtered monoaxial acceleration signal d) using the pitch obtained in each pitch detection as a cut-off frequency to set a low-pass or band-pass filter, and performing low-pass or band-pass filtering on corresponding high-pass filtered monoaxial acceleration signal by using it e) obtaining acceleration signal extreme value points from each low-pass or band-pass filtered monoaxial acceleration signal and removing interfering extreme value points therein f) counting the number of the acceleration signal extreme value points after the interfering extreme value points have been removed g) determining the accumulative walkrun step number of the walkrunner. The method can count steps accurately.