An automatic thermo-luminescence desimeter, comprising a thermo-luminescence dosimeter element which is composed of a card carrying a thermo-luminescence material and contained in an encasing member; a magazine adapted to accommodate therein a plurality of the thermo-luminescence dosimeter elements; means for transporting the magazine; card feeding means for extracting a thermo-luminescence dosimeter element from the magazine and feeding the element into a longitudinal groove formed in a housing; releasing means for releasing engagement between the card and the encasing member; means for feeding the card into a transversal groove formed in the housing; heating means for heating the thermo-luminescence material carried by the card fed to the transversal groove by irradiating with infrared rays; and photoelectric converter means for converting thermo-luminescence emitted by the thermo-luminescence material into an electric signal, whereby doses of exposed radiation of the individual theremo-luminescence dosimeter elements are successively measured within a short time.