An imaging apparatus for diagnosis relating to the present invention is connected detachably with a probe provided with a first transmitting and receiving unit repeating electric signal transmission and reception and a second transmitting and receiving unit repeating optical signal transmission and reception, obtains a reflected signal inside a body cavity from the first or the second transmitting and receiving unit by rotationally operating the first and the second transmitting and receiving units inside the body cavity, and can generate a tomographic image inside the body cavity, in which the apparatus is characterized by including an electric rotary connector 526 carrying out transmission of the electric signal in a state of rotationally operating the first and second transmitting and receiving units； and an optical rotary connector carrying out transmission of the optical signal the electric rotary connector 526 includes a metal surface 522, 523 mounted on the rotational drive unit side and a brush 524, 525 mounted on the fixed unit side, and the brush 524, 525 is operable between a contact position and a non-contact position.
