There are provided: a method for image adjustment using a charged particle beam device, and a charged particle beam system, capable of appropriately adjusting a contrast and brightness as well as a focus for a measurement region present in a deep portion of a sample even when a depth of the measurement region is unknown.
A method for image adjustment performed by a computer system controlling a charged particle beam device includes: by the computer system, specifying a measurement region from a captured image of a sample; performing centering processing based on the specified measurement region; extracting the measurement region in a field of view that has undergone the centering processing or the image that has undergone the centering processing; adjusting a contrast and brightness for the extracted measurement region; and adjusting a focus for the measurement region in which the contrast and brightness have been adjusted.