An imaging apparatus of a radiological imaging apparatus is provided with a first and a second radiation detectors disposed around a hole portion into which a bed is inserted. The first radiation detector includes a detecting portion formed of GaAs of a square having a side of 5 mm and having a thickness of 2 mm. The second radiation detector includes a detecting portion formed of CdTe of a cube having a side of 5 mm. The first radiation detector detects X-rays emitted from an X-ray source and transmitted through an examinee and does not detect γ-rays emitted from the examinee. The second radiation detector detects above X-rays and γ-rays. An X-ray signal processing apparatus processes an X-ray image signal from the first radiation detector and outputs intensity information thereof. A signal discriminating apparatus processes a γ-ray image signal from the second radiation detector and outputs a pulse signal. Thus, the radiological imaging apparatus capable of carrying out radiation examination of the subject by using X-rays and γ-rays can be simplified.