To provide an imaging apparatus that can simultaneously acquire left and right images to acquire good 3D video and can be miniaturized, and an interchangeable lens used for the imaging apparatus.

An imaging apparatus comprises: an imaging element; a first imaging optical system disposed so that its imaging region comes to a first region of the imaging element; and a second imaging optical system disposed so that its imaging region comes to a second region which is at least partially different from the first region of the imaging element, and its optical axis crosses the optical axis of the first imaging optical system at a finite position.