1. A radiological imaging apparatus, comprising: a γ-ray detecting section for outputting γ-ray detection signals, said γ-ray detecting section comprising a plurality of radiation detectors arranged in a longitudinal direction of a bed and around said bed; an X-ray source arranged outside said γ-ray detecting section and being able to be moved in a circumferential direction with respect to the longitudinal direction of said bed; and an X-ray detecting section for outputting X-ray detection signals, said X-ray detecting section being a radiation detectors, wherein said X-ray detecting section is positioned in a region formed between one end and the other end of said γ-ray detecting section in the longitudinal direction of said bed, and one or more gaps through which X-rays irradiated from said X-ray source pass are formed within said γ-ray detecting section, between said radiation detectors arranged in said longitudinal direction of said bed, and wherein said one or more gaps are formed in a circumferential direction with respect to said longitudinal direction of said bed, and said γ-ray detecting section does not move during movement of said X-ray source.