Abstract: Modification of the two roller-hearth heat treatment furnaces located at Xinyu I＆S Co.,Ltd.,Jiangxi Province is conducted to solve such problems as inconsistent heat treatment quality caused by the temperature control via manually adjustment of coal gas flow,rather long heating duration and high exhausted gas temperature due to cold charge The modification involves three major aspects namely,furnace structure,combustion system and temperature control system,and has met the objectives of productivity enhancement,product quality improvement as well as energy saving.