Abstract: C-warp defect caused by residual stress imbalance is an unavoidable shape defect in the production of hot rolled strip, but there is a lack of technical means to control C-warp in actual production. In this paper, the crack compliance method based on the principle of elastic fracture mechanics was used to study the evolution of residual stress in the process of tempering process, and strain reconstruction method based on the flow characteristics of metal in the process was proposed to improve the flatness defects and stress problems of hot rolled strip efficiently and conveniently. Based on the above principles, the improvement mechanism of C-warp defect in hot rolling production was analyzed, and the application case was given.