A position detecting device includes: X-axis electrodes formed by a plurality of conductors that are arranged substantially parallel to each other; Y-axis electrodes formed by a plurality of conductors that are arranged substantially parallel to each other and that extend perpendicularly to the X-axis electrodes; a driving section for supplying an AC signal to the X-axis electrodes; a synchronous clock generating section for generating a synchronous clock at the time when the AC signal passes through zero-cross points; a first change-over switch for selectively supplying the AC signal outputted from the driving section to a predetermined electrode among the X-axis electrodes in response to the synchronous clock; a second change-over switch for selecting a predetermined electrode among the Y-axis electrodes in response to the synchronous clock; a synchronous detector for synchronous-detecting a signal outputted by the Y-axis electrodes through the second change-over switch based on the synchronous clock, and outputting the detected signal; and a position calculating section for calculating a position indicated by an indicator based on the signal outputted from the synchronous detector, the position corresponding to one or more intersections of the X-axis electrodes and Y-axis electrodes.