A positioning device includes a phase calculation section which performs a correlation process of a specific positioning base code replica and a positioning base code from a specific transmission source to calculate a present phase of the positioning base code, an estimated phase calculation section which calculates an estimated phase when estimating the present phase based on the phase used for preceding positioning, a Doppler shift of a frequency of a radio wave carrying the positioning base code, and an elapsed time from the preceding positioning, a phase difference evaluation section which determines whether or not a phase difference between the calculated present phase and the estimated phase is within a phase difference allowable range specified in advance, and a positioning section which locates a present position using the phase within the phase difference allowable range.