Abstract: The relationship between the dynamic characteristics of torsional vibration of the rolling mill system and the quality of the strip was taken into consideration in this paper, then the torsional vibration model of 6-H rolling mill based on continuum dynamics was built, which consists of the rolls system equivalent model and the roll neck transition portion equivalent model. According to the relationship between the rolling speed and the angular velocity of the roll, the relationship between rolling deformation and torsional vibration was established. Based on the proposed model, the three dimensional dynamic responses of rolling mill and strip were simulated. Simulation results show that the roll angular displacement and the angular velocity fluctuate tinily along the roll axial direction; while the distribution of rolling pressure, the backward stress and the forward stress fluctuate to varying degrees by the torsional vibration of the rolls, and the amplitude of the drive side is larger than that of the operation side.