An imaging device is provided with a condition designating unit which designates, by time division, imaging conditions for capturing an image, and light emission conditions for emitting auxiliary light, an imaging section which captures an image including a subject according to the imaging conditions, a light emitting unit which emits auxiliary light with respect to the subject according to the light emission conditions, and an image composer which composes a first image that is captured under a first imaging condition during a light emission period in which the auxiliary light is emitted and a second image which is captured under a second imaging condition during a non-light-emission period which is continuous to the light emission period and in which the auxiliary light is not emitted, in which quality of an image which is captured in a low illumination environment is improved.