In order to take into account the availability of shared location data and privacy protection requirements,aiming at the shared location information collected by the third party,a location privacy protection scheme of LBS users was proposed based on differential privacy.Firstly,the shared location data set was preprocessed,the dictionary query mode was used to build the location transaction database,and the trie tree structure was adopted to store the location data and frequency,so as to improve the query efficiency and reduce the number of noise.Secondly,frequent location selection was carried out in the Trie tree,and Laplacian mechanism under differential privacy was used to disturb the location frequency.Finally,the perturbed data was optimized based on the two techniques of upward post-processing and consistency constrained post-processing,and theoretically prove that the proposed scheme satisfies ε[KG-*4]-differential privacy.The experimental results show that,compared with the existing methods,this scheme improves the efficiency of data processing,generalizes the sensitive locations,and has higher accuracy and lower rejection rate.This scheme has a certain reference value in user location privacy protection and shared location data availability.