It is found that damaged regions are formed around indium contacts to p-type CdHgTe {310} heteroepitaxail layers (HELs) on GaAs substrates and the sizes of these regions depend on the temperature and time of annealing in air. It is shown experimentally that at an annealing temperature of 90 °C, the rate of expansion of the damaged regions is about 4 µm/h, and at temperatures of 120 °C, it is more than 25 µm/h. After 488 hours of annealing of plates of CdHgTe HELs at 60 °C in air, the formation of damaged regions around the indium contacts to the p regions was not observed. The studies were performed on plates of p-type CdHgTe HELs on GaAs substrates whose surface was covered with SiO2 and Si3N4 dielectrics (with a total thickness of about 0.15 µm), with windows where p-n junctions were generated by ion implantation of boron.