Abstract: The open train model is the main coal railway transportation,which brings serious dust pollution to railways.To solve this problem,develope a new type of environmental protection dust covering agent and its automatic spraying system.The system can prepare dust covering agent automatically,meanwhile,online monitor the concentration,viscosity,conductivity,temperature data of covering agent.The spraying amount is regulated automatically according to the train speed.The spraying process can operate well while the train is running.The system applies to different kinds of C type train,it also can identify automatically traction locomotive and mixed train.The system has lots of advantages,such as simple operation,stable running,high automation,low cost and effective.This technology realizes its industrial application in coal railway transportation.