Abstract: The material decomposition of dual-energy CT plays an important role in understanding the material distribution inside the substance. The X-ray energy spectrum distribution used in conventional CT is unknown, and the material attenuation coefficient cannot be obtained from the energy information, and the continuous energy spectrum projection does not match the single-energy reconstruction algorithm. There is an error between the attenuation coefficient of the reconstructed image and the theoretical attenuation coefficient of the material, and the decomposition result is not accurate. To solve the above problems, this paper introduces reference components to obtain equivalent energy information, and then obtains the single energy attenuation coefficient of the material, and introduces the Euclidean distance in the neighborhood space the tolerance restricts the material composition in the material decomposition model, and the Euclidean distance tolerance is obtained from the reconstructed image of the reference component. The experimental results show that the method in this paper can accurately decompose the materials in the detected object on the basis of the conventional CT projection system.