The temperature distribution of the work roll affects the shape and size of final product in aluminum strip cold rolling process. The segmental model is presented to explore the boundaries of the roll. The surface of the work roll is divided into 5 different regions including the outlet roll-strip contact region, the inlet roll-strip contact (bite) region, the roll-spray region, the roll-air region and the roll-roll contact region. Based on the analysis of the roll pressure, the mathematical models of the plastic doformation work and friction heat are proposed to calculate the temperature variation in bite region. The boundaries, including heat convection with lubricant/air and heat conduction with the backup roll, are considered to model the work roll’s temperature distribution.