Abstract: Train tracking interval is closely related to the train operation of high-speed railway, the effect of train traction characteristics, line conditions and other factors on train tracking interval can be tested by simulation system, which provides effective support to the study about high-speed railway train tracking interval optimization and train technical operation. This paper introduced the design of simulation system for train tracking interval of high-speed railway, through standardized calculation method of train tracking interval, combined with the data of train traction computing, station and line, etc., a prototype system was developed, which implemented the calculation and simulation of train running curve and train tracking interval. The System structure, function design and data structure were presented in detail, and an example was used to validate the system function and feasibility. The output data were consistent basically with the actual situation in our country, the system could be used as a reliable tool for the study of train tracking interval.