Au-doped Hg1-xCdxTe epitaxial layer materials were grown by using a vapor phase epitaxial method. The layer materials were characterized by a Fourier spectrometer and a metallographic microscope. The longitudinal distribution trend of Au in the Hg1-xCdxTe epitaxial layer and CdZnTe substrate was analyzed by Secondary Ion Mass spectrometry (SIMS). In addition, the longitudinal distribution trend of I and II impurities and VI and VII impurities in the Hg1-xCdxTe epitaxial layer and CdZnTe substrate was also analyzed by SIMS. It was found that the transition region between the substrate and the epitaxial layer can absorb the impurities. This result is of significance to the improvement of detectors in performance.