Intracranial pressure estimating method and intracranial pressure estimating device

This intracranial pressure estimating method includes: an acquisition step (S10) of acquiring time-series data of an external ear canal pressure pulse wave of a subject; an analysis step (S12) of analyzing external ear canal pressure pulse wave data obtained by digitizing the time-series data of the external ear canal pressure pulse wave, and calculating a first formant frequency of the external ear canal pressure pulse wave data; a correction step (S13) of correcting the calculated first formant frequency on the basis of personal information relating to the subject, to calculate a corrected value; and an estimation step (S14) of calculating an estimated value of the intracranial pressure on the basis of the corrected value that has been calculated.