A configuration is provided for firmly fixing a transmitting and receiving unit for IVUS and a transmitting and receiving unit for OCT in a probe of an imaging apparatus for diagnosis in which space saving is achieved. According to the present invention, the probe includes a cylindrical housing 223 in which an ultrasonic wave transmitting and receiving unit 310 is arranged on a distal side and a light transmitting and receiving unit 320 is arranged on a proximal side. Two signal wires 311 of which one ends are connected to the ultrasonic wave transmitting and receiving unit 310 and which extend toward the proximal side substantially parallel to each other are arranged in the housing 223 so as to cause the distance between the two signal wires to be smaller than a width W of a ball lens portion 322 configuring the light transmitting and receiving unit 320 below the light transmitting and receiving unit 320.
