It is possible to determine an optimal parasitic aberration adjustment amount even when the relationship of the parasitic aberration adjustment amount with respect to the field intensity of multiple poles changes nonlinearly. To this end, in the present invention, an aberration correction amount is computed by measuring an aberration coefficient of an optical unit of a charged particle beam device, and at the same time, the present value of a power supply control value applied to an aberration corrector is measured. Then, the parasitic aberration adjustment amount for suppressing the amount of a parasitic aberration generated in the aberration corrector is computed on the basis of the aberration correction amount and the present value of the power supply control value.