Abstract: A charged particle beam device according to the present invention comprises a charged particle source that emits charged particles, a detection circuit that detects electrons which are generated by a sample as a result of irradiation with the charged particles, and a power storage device (107_VHD) that holds direct voltage, and comprises a charge circuit (107_CHG) that charges the power storage device with supplied voltage, and a control circuit (107_CTL) that controls the charge circuit such that charging is carried out in a period in which no sample is measured, wherein the direct voltage held by the power storage device (107_VHD) is used as operating voltage.