Research conclusions：After the passenger dedicated line network is formed, the passenger traffic service of the existing lines will reduced much, and plenty of passenger stations and mixed passenger and freight service stations will be changed into freight stations. In that case, the freight traffic capacity of the existing line will enhance, the train type on the line will reduce, the speed difference between trains will lower, the travel speed of train will enhance, and the coefficient of removal for scheduling one passenger train will reduce, so based on this situation, the existing line should explore its traffic capacity to meet the increasing traffic demand. At the same time, the existing line should well coordinate the relation between it and the passenger dedicated line, adjust its traffic organization principle, upgrade its infrastructure, pay more attention to the quality of freight traffic, grasp the development chance, full give play to its advantages, accurately aim at the market target, and develop its characteristic passenger and freight traffic products to enhance its competition capacity for meeting the increasing traffic demand.