There is provided a technique capable of eliminating the need to create data for compensating the displacement of a servo pattern occurring at the time of writing the servo pattern using an amplitude method and thereby of significantly reducing the production time of a disk medium. A servo pattern writing apparatus that uses a write head to write a servo pattern on a recording medium according to an amplitude method, comprises: a position sensor that detects the displacement amount of the write head with respect to its reference position in the track crossing direction; and a delay amount adjustment circuit that writes a servo pattern in correspondence with a servo pattern write phase amount which is set for compensating the displacement amount detected by the position sensor at the time of demodulation of the servo pattern.