CdZnTe(211)B substrate is widely used for the growth of mercury cadmium telluride(HgCdTe) by molecular beam epitaxy,and the quality of HgCdTe grown by MBE depend strongly on the performance of the substrates.The effect of several key parameters of CdZnTe(211)B substrate on the HgCdTe epitaxial materials is discussed,including Zn composition and uniformity,defects(dislocation,grain boundary and Te precipitates) and surface condition(roughness and chemical composition).And the characterization methods and indexes of the parameters are analyzed when CdZnTe(211)B substrates are screened.