A magnetization method and a magnetization apparatus for forming an objective magnetized state in a one-dimensional region of a magnetic body, and a magnet for a magnetic encoder. In the magnetization method, magnetism in one direction is applied to an entire half wavelength interval of a sine wave on the magnetic body by a magnetizing yoke and a magnetized state of a first-order rectangle wave or of a first-order trapezoidal wave is formed in the interval, the magnetized state presenting polarity information in a rectangle or trapezoidal pulse shape; and thereafter, magnetism in opposite direction is applied to a start point and a terminal point of the interval by the same magnetizing yoke or a different magnetizing yoke one time or several times and the magnetized state of the first-order rectangle wave or of the first-order trapezoidal wave is changed into the objective magnetized state.