According to the advantages and disadvantages of the user behavior trajectory in the most widely used networks such as Google search, Taobao and Happy Network，that the passive service model of“user seeking information”is changed into the active service model of“information seeking users”is presented，the corresponding data information collection method is built by clickstream research，the user trajectory research construction including six model systems such as collection，analysis，recommendation，evaluation，feedback and abstraction is built，three application scenarios such as application content recommendation，concerned application recommendation and aided important application security are analyzed，and the case analysis and application for user behavior trajectory reconstruction is conducted.