In the present work, some thermoluminescent properties of chemically vapour deposited (CVD) polycrystalline diamond films are investigated. After radiation, two TL peaks at least located at 350 and 540 K are observed. After depletion of the low temperature peaks, the 540 K TL peak is isolated and then analysed by different methods; an energy level at around 0.9 eV is found. It is shown that, when it is grown under particular conditions, CVD diamond possesses some dosimetric properties like TL sensitivity to ? radiation, X rays and ß doses, a glow peak at 540 K which was isolated, a green luminescence band at 500 nm and non-sensitivity to UV exposure wavelengths above 230 nm.