Several photosensitive materials of Chinese make have been used for the whole- body autoradiography of the tritium labelled and freeze-drid sections of mice.1 mCi of tritiated water was injected peritoneally into each mouse.Sections prepared from the mouse were placed in direct contact with fast X-ray films for ihdustrial use,made in Tianjin.After 22 days of exposure,satisfactory autoradiographs were obtained.When the X-ray film for medical use,made in Shanghai,was tried,no satisfactory autoradi- ograph was obtained after 30 days of exposure.Besides,the dry plate prepared in our laboratory from Nuclear Emulsion №4.has also been tried,but only an incomplete outline was seen on the autoradiograph even after 124 days of exposure.