Abstract: In this research, the thermodynamic and phase diagrams of binary semiconductors compounds ZnTe and CdTe and also the ternary compound Zn-Cd-Te were established. For this purpose, the regular associated solution theory was used in all cases except the one of the solid phase of the ternary compound, where we have used the pseudo-regular associated solution model. The equilibrium diagrams are calculated by the numerical resolution of the free enthalpy equations for different phases.