Abstract: The launching nose plays an important role in the incremental launching construction. The parameters of the launching nose essentially affect the internal forces of the girder during the construction. The appropriate parameters can decrease the internal forces in the girder and save the material and reduce the cost. Based on the simplified structural model, which is built with displacement method according to the characteristic of incremental launching construction and the variation rule of the internal forces, the effect of the length, the stiffness and weight of launch nose on the internal forces of girder during the incremental launching construction are calculated and analyzed. The method, which can calculate the launching nose parameters for the optimum incremental launching construction, is developed. This method is simply and reliable and easy for practical use.