This paper explains the algorithm of similarity calculation: K-means [1] clustering algorithm and Apriori algorithm, achieves the similarity calculation between two or more trajectories by using these two algorithms. Developing this system in the b / s structure model based on similarity calculation. This paper mainly describes system general design and system implementation. Among them, system general design includes the main business design of the system, system function module and database design; system implementation includes the setting of software and hardware and system function.This paper ends with a conclusion and prospect, pointing out problems and inadequacies, discussing the questions of the system functions, algorithm optimization and the like.