To provide a method and device by which a polarized material having a large quantity of polarization can be manufactured easily without dipping a polarized material in insulating oil.

In the method of manufacturing polarized material, the polarized material is obtained by polarizing a material to be polarized by causing an electric field to act on the material in a high-pressure gas of ≥0.2 MPa in pressure. The polarized material manufacturing device is provided with a means which can generate the electric field, a means which can arrange the material to be polarized in the electric field, and a means which can form a high-pressure gas atmosphere of ≥0.2 MPa in pressure at the arranged spot of the material on which the electric field is caused to act.