A radiation irradiating apparatus includes: a radiation generator that generates radiation; a collimator that controls an irradiation range of radiation generated in the radiation generator; and a distance assuring portion having an abutting member that abuts on a subject to be irradiated with the radiation, when the radiation generator and the subject approach each other such that a distance therebetween is smaller than a preset distance. The distance assuring portion assures a distance between the radiation generator and the subject. The collimator and the distance assuring portion form an integral structure and are attachable and detachable with respect to the radiation generator.