The invention relates to a thermal treatment process for high-carbon chromium bearing steel. The thermal treatment process includes the steps that a bearing part is put in a hardening furnace with the temperature raised to 850 DEG C to 870 DEG C first to be kept for 5 min to 15 min, and austenitizing is conducted to obtain a uniform austenite structure; and then the bearing part is put in quenching oil with the temperature of 100 DEG C to 160 DEG C to be kept for 10 min to 60 min, martensite quenching is conducted to obtain a martensitic structure, an appropriate quantity of retained austenite structure is reserved, and then the martensitic structure and the retained austenite structure are put in a tempering furnace to be subjected to two times of stabilizing treatment. In the first time of stabilizing treatment, the furnace temperature is regulated to 80 DEG C to 100 DEG C and kept for 30 min to 60 min, the retained austenite structure is aged and stabilized to obtain the quantity of retained austenite structure required when a bearing is used; and then the second time of stabilizing treatment is conducted, and the furnace temperature is regulated to 150 DEG C to 180 DEG C and kept for 90 min to 150 min. The content of the retained austenite structure in the bearing part can range from 15% to 35%, the fracture toughness and the contact fatigue strength of materials can be greatly improved, and the service life can be prolonged.