In view of the above-mentioned problems, an object of the present invention is to provide a processing method that is not dependent on the material or the ion beam irradiation angle. In order to achieve the object above, the present invention provides a processing device that processes a sample by irradiating the sample with an ion beam, the processing device comprising a sample tilting/rotating mechanism that rotates/tilts the sample relative to the ion beam, wherein the sample rotating mechanism comprises a rotating shaft that rotates the sample relative to the ion beam, and a tilting shaft that is orthogonal to the rotating shaft and that tilts the sample relative to the ion beam, the sample rotating mechanism being adapted to simultaneously perform the rotating and tilting of the sample.