A specimen loading method for loading a specimen that contains water into a specimen chamber of a charged particle beam device, includes: a step (S100) of mounting the specimen on a specimen support; a step (S102) of covering a predetermined area of the specimen with a water retention material; a step (S104) of evacuating the specimen chamber in which the specimen having the predetermined area covered with the water retention material is placed; and a step (S106) of exposing the predetermined area covered with the water retention material.