A positioning method includes (a) executing a cumulative addition for either one of the polarities on each of an I Q components of0 a received positioning signal, which is spread-modulated with a spread code reversed in polarity by navigation data, (b) calculating sum of squares of the result of the cumulative addition, (c) calculating correlation between the sum of squares and a replica code of the spread code, and (d) executing a positioning calculation of the present location based on the result of the correlation calculation.