Six kinds (yellow, green, light blue, purple, grey and blue) are chosen from sixty kinds of dyeing polyethylene terephthalate films, and the absorption spectrum, the wavelength of optical absorbance reading, the dose range and the precision limits for these films are studied. The stability of these systems before and after irradiation, the effects of temperature and relative humidities during irradiation on the response are exanined. The response curves and thier experience expression are give under controlled experimental conditions. The results show that these films can be applied to routine dosimetry in radiation processing with gamma radiation. The yellow film is the best one of the six and its dose range is 0.1~3.5 ×10,3,kGy.