Provided is a charged particle beam device that prevents the increase in processing trouble caused by deterioration in the reviewing performance (e.g., overlooking of defects) by detecting an operation abnormality affecting the performance of the device or a possibility of such an abnormality in the middle of a processing sequence of a sample and giving a feedback in real time. In each processing step of the charged particle beam device, monitoring items representing the operating status of the device (control status of the electron beam, an offset amount at the time of wafer positioning, a defect coordinate error offset amount, etc.) are monitored during the processing sequence of a sample and stored as history information. In the middle of the processing sequence, a comparative judgment between the value of each monitoring item and the past history information corresponding to the monitoring item is made according to preset judgment criteria. When the width of fluctuation from the past history information deviates from a reference range, an alert is issued.