A complex diagnostic apparatus comprising: an ultrasound probe configured to transmit and receive an ultrasonic beam toward and from a subject; an ultrasound image generator configured to generate an ultrasound image based on reception signals outputted from the ultrasound probe; a radiation source disposed so that its placement angle is variable and configured to emit radiation toward the subject; a radiographic image generator which is disposed on a side of the subject opposite from the radiation source so that its placement angle is variable, which has a planar detection surface detecting the radiation emitted from the radiation source and which is configured to form a radiographic image according to a dose of a radiation detected on the detection surface; a first angle sensor provided in the ultrasound probe to detect a placement angle of the ultrasound probe; a second angle sensor provided in the radiation source to detect a placement angle of the radiation source; a third angle sensor provided in the radiographic image generator to detect a placement angle of the radiographic image generator; and an optimal value calculator configured to calculate, based on angle information obtained from the first angle sensor, a direction of transmission of the ultrasonic beam transmitted from the ultrasound probe, and a radiation source optimal angle of the radiation source at which a direction of radiation emitted from the radiation source is substantially parallel to the calculated direction of transmission of the ultrasonic beam and an optimal detection angle of the radiographic image generator at which a normal of the detection surface of the radiographic image generator is substantially parallel to the calculated direction of transmission of the ultrasonic beam, wherein radiation is emitted from the radiation source the placement angle of which has been adjusted to the radiation source optimal angle based on angle information obtained from the second angle sensor and the radiation is detected with the detection surface of the radiographic image generator, a placement angle of which has been adjusted to the optimal detection angle based on angle information obtained from the third angle sensor. an ultrasound probe configured to transmit and receive an ultrasonic beam toward and from a subject; an ultrasound image generator configured to generate an ultrasound image based on reception signals outputted from the ultrasound probe; a radiation source disposed so that its placement angle is variable and configured to emit radiation toward the subject; a radiographic image generator which is disposed on a side of the subject opposite from the radiation source so that its placement angle is variable, which has a planar detection surface detecting the radiation emitted from the radiation source and which is configured to form a radiographic image according to a dose of a radiation detected on the detection surface; a first angle sensor provided in the ultrasound probe to detect a placement angle of the ultrasound probe; a second angle sensor provided in the radiation source to detect a placement angle of the radiation source; a third angle sensor provided in the radiographic image generator to detect a placement angle of the radiographic image generator; and an optimal value calculator configured to calculate, based on angle information obtained from the first angle sensor, a direction of transmission of the ultrasonic beam transmitted from the ultrasound probe, and a radiation source optimal angle of the radiation source at which a direction of radiation emitted from the radiation source is substantially parallel to the calculated direction of transmission of the ultrasonic beam and an optimal detection angle of the radiographic image generator at which a normal of the detection surface of the radiographic image generator is substantially parallel to the calculated direction of transmission of the ultrasonic beam, wherein radiation is emitted from the radiation source the placement angle of which has been adjusted to the radiation source optimal angle based on angle information obtained from the second angle sensor and the radiation is detected with the detection surface of the radiographic image generator, a placement angle of which has been adjusted to the optimal detection angle based on angle information obtained from the third angle sensor.