In order to provide a charged particle beam apparatus capable of stably detecting secondary particles and electromagnetic waves even for a non-conductive sample under high vacuum environment and enabling excellent observation and analysis, the charged particle beam apparatus includes a charged particle gun (12), scanning deflectors (17 and 18) configured to scan a charged particle beam (20) emitted from the charged particle gun (12) onto a sample (21), detectors (40 and 41) configured to detect a scanning control voltage input from an outside into the scanning deflectors, an arithmetic unit (42) configured to calculate, based on the detected scanning control voltage, irradiation pixel coordinates for the charged particle beam; and an irradiation controller (45) configured to control irradiation of the sample with the charged particle beam according to the irradiation pixel coordinates.