A method for inspecting a settling time of a deflection amplifier includes setting a settling time, performing shooting a plurality of times alternately to project two patterns of different types which are shaped by making a charged particle beam pass through a first and a second apertures while deflecting the charged particle beam by a deflector controlled by an output of a deflection amplifier which is driven based on the settling time having been set, measuring beam currents of the shooting, calculating an integral current of the beam currents measured, and calculating a difference between the integral current calculated and a reference integral current to output the difference.