Abstract: High efficient numerical models that can simulate the behaviors of an entire structural system are very important to the study on the fire-induced progressive collapse of RC frame structures. A fire-induced collapse simulation program is developed, which is based on the fiber beam model and the multi-layer shell model. The constitutive models of materials at high temperature are discussed. And the accuracy of the program in simulating RC members in fire is verified by test results. At last, the progressive collapse of an 8-storey frame in fire is simulated and the mechanism of collapse is discussed.