Dislocations in heterostructures CdTe/ZnTe/GaAs(013) and CdTe/ZnTe/Si(013) were investigated using selective etching and transmission electron microscopy. The calculations of critical film thickness hc were fulfilled for 12 various slip systems, the experimental results were obtained for 4 of them. Misfit dislocations are introduced in a ZnTe film at the stage of formation of the first monolayers. With their introduction, the crystal lattices of the substrate and the film unfold relative each other that is confirmed by X‐ray diffraction measurements. An increase in the dislocation density into the CdTe and HgCdTe films was observed using layer‐by‐layer etching. That is testifies to the annihilation of threading dislocations during the growth of CdTe and MCT films. The dislocation annihilation rate is higher in films grown on GaAs(013) than on Si(013). Perhaps this is due to the higher proportion of gliding dislocations in CdTe films on GaAs substrates (013). It was made annealing of MCT films under cyclic temperature change in such way that activity of MCT components was changed to enhance the non‐conservative motion of dislocations. As a result, the density of penetrating dislocations in the active areas in MCT films on silicon substrates was decreased to the value of 2.5×106 cm‐2.