The present invention realizes a composite charged particle beam apparatus capable of suppressing a leakage magnetic field from a pole piece forming an objective lens of an SEM with a simple structure. The charged particle beam apparatus according to the present invention obtains an ion beam observation image while passing a current to a first coil constituting the objective lens, and performs an operation of reducing the image shift by passing a current to a second coil with a plurality of current values, and determines a current to be passed to the second coil based on a difference between the operations.