A radiation detection apparatus including a casing, and a radiation detection device accommodated inside the casing, which detects radiation emitted from a radiation source and having passed through a subject, and converts the radiation into radiation image information, and an electronic circuit accommodated inside the casing, further comprising: storage device detachably mounted with respect to the casing, and wherein the electronic circuit includes a data compression circuit, which compresses the radiation image information, to thereby create compressed radiation image information, and herein the storage device stores the compressed radiation image information.