A work machine control method includes: acquiring a detection position of a landmark detected by a non-contact sensor provided in a work machine in traveling of the work machine traveling on a traveling path; calculating a first relative distance between the non-contact sensor and the landmark on a basis of the detection position of the landmark; calculating a second relative distance between the non-contact sensor and the landmark on a basis of a registration position of the landmark; calculating a correction value relating to a relative distance between the non-contact sensor and the landmark on a basis of the first relative distance and the second relative distance; correcting the first relative distance on a basis of the correction value to calculate a corrected relative distance between the non-contact sensor and the landmark; and controlling a traveling state of the work machine on a basis of the corrected relative distance.