A coordinate detecting device includes a detecting unit configured to detect the capacitance of each of a plurality of electrodes arranged in a predetermined direction and an arithmetic processing unit configured to calculate the coordinates of a detection target using different calculation methods according to the state of a variation in the capacitance of the plurality of electrodes. The arithmetic processing unit calculates the coordinates of the detection target, using one of a centroid calculation method of calculating the coordinates of the centroid and a curve approximation method of calculating a peak of a curve according to a comparison value between a capacitance variation of a peak electrode and a capacitance variation of an electrode which is not adjacent to the peak electrode.