Provided is an image-acquisition apparatus (1) including an objective lens (2) consisting of, in order from an object side, a first group (G1) and a second group (G2), an image-acquisition device (3) that converts an optical image of an object formed by the objective lens (2) into an electrical signal, a first holding frame (4) holding the first group (G1) of the objective lens (2) inside, and a second holding frame (5) integrally holding the second group (G2) of the objective lens (2) and the image-acquisition device (3) inside. The objective lens (2) satisfies conditions (1) and (2): where f_front is a focal length of the first group (G1), f_rear is a focal length of the second group (G2), and f is a focal length of the entire objective lens (2).
