To increase the efficiency of exhaust heat and suppress noise in an X-ray CT apparatus.SOLUTION: An X-ray CT apparatus includes a frame device having a rotating frame for rotating an X-ray tube and an X-ray detector. The frame device includes: a front cover that has two layers of a first outer member serving as a front exterior and a first inner member located therein, sucks outside air from a first air inlet formed in the first outer member, and flows outside air into an accommodation space inside the first inner member in which the rotating frame is accommodated through a first gap space between the first outer member and the first inner member； and a rear cover that has two layers of a second outer member serving as a rear exterior and a second inner member located therein, sucks outside air from a second air inlet formed in the second outer member, and flows outside air into the accommodation space through a second gap space between the second outer member and the second inner member.SELECTED DRAWING: Figure 1【課題】Ｘ線ＣＴ装置において、排熱の効率を向上するとともに騒音を抑制する。【解決手段】Ｘ線ＣＴ装置はＸ線管及びＸ線検出器を回転させる回転フレームを有する架台装置を備える。架台装置は、前面の外装となる第１外側部材と、その内側に位置する第１内側部材との２層を有し、第１外側部材に形成された第１吸気口から外気を吸気し、第１外側部材と第１内側部材との間の第１間隙空間を介して回転フレームが収容される第１内側部材の内側の収容空間へと外気を流入する、フロントカバーと、後面の外装となる第２外側部材と、その内側に位置する第２内側部材との２層を有し、第２外側部材に形成された第２吸気口から外気を吸気し、第２外側部材と第２内側部材との間の第２間隙空間を介して収容空間へと外気を流入する、リアカバーと、を備える。【選択図】図１
