The invention relates to a bainite quenching process method for a GCr15 steel small thin-walled bearing sleeve ring. The method comprises the following steps that (1) the GCr15 steel small thin-walledbearing sleeve ring is placed in a material tray and enters a bainite production line; (2) heating is conducted; (3) salt bathing and quenching are conducted; and (4) bainite isothermal quenching isconducted; and the bainite production line is the 750mm Mabe production line manufactured by the AICHELIN company, a salt stirring device is arranged in a salt bathing and quenching tank, the salt used in the salt bathing and quenching tank and a bainite salt bathing isothermal tank is the mixed nitrate composed of sodium nitrite and potassium nitrate with the weight ratio of 1:1. The bainite quenching process method has the beneficial effects that bainite quenching processing can be conducted on the GCr15 steel small thin-walled bearing sleeve ring with the outer diameter size being 50-80 mmon the bainite production line, so that the deformation rate of a workpiece after bainite isothermal quenching is reduced to 2-3% from the original 30%.