A charged particle beam apparatus includes a charged particle beam column for irradiating a sample with a charged particle beam, and a sample stage unit for moving the sample relative to the charged particle beam column. The sample stage unit includes a rotary stage section having a base portion and a rotary mover rotatable about a rotary axis relative to the base portion. A rotary connector is disposed coaxially with and rotatable about the rotary axis and fitted between the base portion and the rotary mover for electrically connecting wirings between relatively rotating elements. A connection electrode is disposed on the sample stage unit in electrical connection with the rotary connector. In the charged particle beam apparatus, the sample is able to be rapidly placed and replaced.