Abstract: In the field usage,there are many inactivation problem on the Cr-Ni-Mo chilled iron Ⅳ roller. By the sampling and analysis in the field,based on the laboratory experiments which included the series temperatures aging tests and the abradability tests,finally,established the relation on the heat-treatment condition and the property. By the stress relieving under the heat-treatment of the temperature,(425±5)℃,the Cr-Ni-Mo chilled iron Ⅳ composite roller can obtain the optimal property adaption and usage effect. That makes the width of rolling strip steels increased by more than 10%,then solve the quality problems of roller in the practice production and provide the conditions to increase product specifications for the user,affirmed by the user.