1. A radiation-type diagnosis apparatus wherein a recording sheet is used for receiving the radiation passing through a region of interest of an object and photographing the image of this region, along with a bar code identifying the recording sheet, said diagnosis apparatus comprising: radiation-generating means for generating radiation; support means for supporting a subject and defining a recording region; first storage means for storing a number of recording sheets; sheet-supplying means for supplying said recording sheets, one by one, from said the first storage means to said recording region; second storage means for storing the recording sheets exposed to the radiation in said recording region; bar code-reading means located within said second storage means, for reading data from the bar code provided on each of the recording sheets; and position-detecting means incorporated within said first storage means, for detecting the presence or absence of a bar code on each recording sheet stored in said first storage means, thereby to determine whether or not the recording sheet is positioned correctly in said first storage means, wherein the recording sheet held in said recording region is exposed to the radiation passing through a region of interest of the object, an image of the region of interest is thereby photographed on the recording sheet, the recording sheet is scanned with a light beam, thereby reproducing the image of the region of interest, and the reproduced image and the data read from the bar code are used in diagnosing the region of interest.