A charged particle beam device is provided that performs proper beam adjustment while suppressing a decrease in MAM time, with a simple configuration without adding a lens, a sensor, or the like. The charged particle beam device includes: an optical element which adjusts a charged particle beam emitted from a charged particle source; an adjustment element which adjusts an incidence condition of the charged particle beam with respect to the optical element; and a control device which controls the adjustment element, wherein the control device determines a difference between a first feature amount indicating a state of the optical element based on the condition setting of the optical element, and a second feature amount indicating a state where the optical element reaches based on the condition setting and executes adjustment by the adjustment element when the difference is greater than or equal to a predetermined value.