Aim. Study of the kinetics of oxidation of zirconium alloy Zr-1% Nb and Zr with heating in air, depending on the heating rate and processing time. Method. Zirconium alloy Zr-1% Nb and zirconium of vacuum remelting were chosen as the material of the studies. For the thermal treatment, a laboratory electric furnace SNOL30/1300 was used. The heating rate was varied from 2.5°C/min. up to 20°С/min., and cooled together with the furnace.