Abstract: Cadmium zinc telluride(Cd1-xZnxTe, CZT) crystals are of significant value in infrared detection and nuclear radiation detection due to their wide band gap, high photoelectric absorption efficiency, and excellent energy resolution. This study investigates the effects of synthesis temperature, holding time, and pressure on the purity and homogeneity of CZT polycrystalline materials using high-pressure synthesis technology. The experimental results demonstrate that the optimal process parameters are a synthesis temperature of 1 130 ℃, holding time of 6 h, and pressure of 4.0 MPa, under which ultrapure CZT polycrystalline material with a purity of up to 7N can be obtained. The optimized process effectively suppresses Te volatilization, reduces the quality fraction content of impurities such as Fe, Ni, and B to below 0.5×10^(-6)%, and improves the homogeneity of Zn element distribution.