The molecular beam epitaxial growth conditions and component adjustment of CdSexTe1-x substrate material for HgCdTe infrared detectors are briefly introduced. Growth conditions include growth structure (mainly CdSexTe1-x/CdTe/ZnTe/Si, CdSexTe1-x/ZnTe/GaAs, etc.), growth temperature (about 300℃), and growth thickness (about 5 m ), etc. Component adjustment includes analyzing the changes of Se components with (JSe+JTe)/JCd and JSe/(JSe+JTe). When the JSe/(JSe+JTe) value is small, it is difficult for the Se component to incorporate into the epitaxial layer. When the JSe/(JSe+JTe) value is large, the Se component increases rapidly. At the same time, when the JSe/(JSe+JTe) value is small, the growth trend of the Se component is relatively easy to control. When the value of JSe/(JSe+JTe) is constant, the Se component increases with the decrease of (JSe+JTe)/JCd. The sudden increase point of Se component change increases with the decrease of (JSe+JTe)/JCd value. This paper can provide some reference for the preparation of high-performance HgCdTe infrared detectors.