Abstract：In order to study the effect of radiation dose to rare traditional Chinese medicine composition, Fourier transform infrared spectra and their second derivative spectra of Hippocampus trimaculatus Leach powder irradiated by 0, 1.5, 3, 4.5, 6, 9,12，15, 18, 19.5 and 21 kGy were studied. Protein is the main component of Hippocampus trimaculatus Leach powder, and the content is more than 70%. It was shown that the infrared spectrum of the protein and lipid absorption in sample band doesn〖KG-*4〗’t change when it was irradiated by 1.5, 3, 4.5 and 6 kGy. But the infrared spectrum of sample had obvious change when it was irradiated by higher than 9 kGy in intensity; Irradiation had little effect on the protein secondary structure of sample if irradiation is not more than 9 kGy; Irradiation had greater effects on the protein secondary structure if it is higher than 9 kGy. It is feasible if Hippocampus trimaculatus Leach powder was irradiated by no more than 9 kGy. Research results provides a reference on irradiation dose setting of Hippocampus trimaculatus Leach powder for nuclear irradiation companies.
