To provide a step number measuring apparatus in which a reduction in electric power is intended by a simple constitution, and which can correspond to plural movements. A CPU calculates a moving motion pitch on the basis of a detection signal from sensors that a switching circuit has selected, calculates the moving motion pitch by performing a processing having been selected from among plural kinds of processings, which have been stored in a memory, on the basis of the detection signal from the sensors that the switching circuit has selected, calculates the moving motion pitch by selecting the other processing among the plural kinds of processings when both the moving motion pitches differ, and performs a step number measurement by the selected processing when both the moving motion pitches become the same.