Abstract: In order to achieve the organic integration of various businesses in freight marketing and optimize the railway freight marketing model, this paper designed a railway freight marketing big data system and elaborated on the overall architecture of the system. The paper implemented functions such as customer relationship management, integrated assessment management, analysis and decision-making management, and market monitoring through data collection dispatching technology and machine learning based predictive analysis technology. The system has been launched and applied in China Railway Jinan Group Co. Ltd., achieved significant improvement in economic benefits, effectively enhanced the level of freight production organization, and provided technical support for various marketing decisions of the freight department.