According to one aspect of the present invention, a multi-beam image acquisition apparatus, includes: an objective lens configured to image multiple primary electron beams on a substrate by using the multiple primary electron beams; a separator configured to have two or more electrodes for forming an electric field and two or more magnetic poles for forming a magnetic field and configured to separate multiple secondary electron beams emitted due to the substrate being irradiated with the multiple primary electron beams from trajectories of the multiple primary electron beams by the electric field and the magnetic field formed; a deflector configured to deflect the multiple secondary electron beams separated; a lens arranged between the objective lens and the deflector and configured to image the multiple secondary electron beams at a deflection point of the deflector; and a detector configured to detect the deflected multiple secondary electron beams.