Problem to be solved: to provide an indoor sterilizing apparatus for surely sterilizing bacteria adhering to various places such as floating bacteria floating in an indoor space and floor surfaces, walls, and surfaces of objects.Solution: the indoor sterilizing apparatus 1 is provided with a housing 21, a wall surface of an indoor wall, a mounting part 5 for mounting a housing on a wall surface of a persons height higher than the height of the person, and an ultraviolet ray which is provided in the casing 21 and below the horizontal direction relative to the floor surface The control unit 6 is provided with a control unit 6 for controlling the irradiation of ultraviolet rays by the lower irradiation unit 3 based on the presence or absence of the lower irradiation unit 3 and the human body in the room.Diagram【課題】室内空間を浮遊する浮遊菌および、床面、壁面、物体の表面などの様々な場所に付着している付着菌を、確実に殺菌する室内殺菌装置を提供する。【解決手段】室内殺菌装置1は、筐体21と、室内の壁面であって、人の身長より高い場所の壁面に筐体を取り付けるための取付部5と、前記筐体21に設けられ、床面に対する水平方向よりも下方に紫外線を照射可能な下方照射ユニット3と、前記室内の人体の存在又は不存在に基づいて、前記下方照射ユニット3による紫外線の照射を制御する制御部6を備える。【選択図】図1