To provide a microscope device allowing external phase difference observation and able to shorten the entire length of an optical system.

The microscope device 10 comprises: a light source 1; a diaphragm 2 with an aperture 2a; a condenser lens 3 for making light from this aperture 2a substantially parallel and emitting the substantially parallel light to a sample H; an objective lens 4 for imaging light passed through the sample H; a first micro-lens array 5 arranged on a primary image face F3 of the sample H; and a second micro-lens array 6 arranged on the image side from this first micro-lens array 5, and on a surface F4 in conjugation with the exit pupil surface of the objective lens 4. The second micro-lens array 6 is configured such that a unit lens set 6b formed from a plurality of unit lenses 6a dividing a luminous flux emitted from each unit lens 5a of the first micro-lens array 5 are two-dimensionally arranged. In addition, the unit lens 6a of each of this unit lens set 6b, which is located in conjugation with the aperture 2a of the diaphragm 2, is provided with a phase film.