An imaging apparatus comprises: an imaging optical-system that includes a first optical-system and a second optical-system having imaging characteristics different from each other and being arranged concentrically; and an image sensor that has a plurality of pixels composed of photoelectric conversion elements two-dimensionally arranged, respectively pupil-divides light incident through the optical-systems, and selectively receives the light by the pixels. With the imaging apparatus, the light amount of the light incident on the image sensor through each of the optical-systems is adjusted, and interference is prevented. The imaging apparatus further comprises a stop including an annular light blocking section of which an inner diameter and an outer diameter can be increased or decreased, and adjusting a light amount of light passing through each of the optical-systems by increasing or decreasing the inner diameter and the outer diameter of the light blocking section at a boundary between pupil regions of the optical-systems.