An imaging apparatus is disclosed for diagnosis generating a first tomographic image and a second tomographic image inside a lumen of a measurement subject body by using an ultrasound signal which is transmitted and received by a first transmitting and receiving unit and an optical signal which is transmitted and received by a second transmitting and receiving unit in a case where a transmitting and receiving unit in which the first transmitting and receiving unit performing transmission and reception of the ultrasound signal and the second transmitting and receiving unit performing transmission and reception of the optical signal are disposed moves in an axial direction while rotating in the lumen of the measurement subject body.