A charged particle beam apparatus includes: a stage on which a sample is placed; a first charged particle beam unit comprising a charged particle source, a detector, and a first objective lens configured to irradiate a sample with a charged particle beam of charged particles generated by the charged particle source and induce secondary electrons generated from the sample to the detector; and a second charged particle beam unit comprising a second objective lens. An incoming electric field is generated between the first objective lens and the sample to pull the secondary electrons into the first objective lens. An induced electric field is generated between the second objective lens and the sample to guide the secondary electrons to travel to the detector.