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, this paper proposes a location privacy protection scheme of LBS users based on differential privacy. First of all, the Shared location data set is preprocessed and Trie tree structure is adopted to store location data and frequency. Secondly, frequent location selection is carried out in the Trie tree, and Laplacian mechanism under differential privacy is used to disturb the location frequency. Finally, we optimize the perturbed data based on the two techniques of upward post-processing and consistency constrained post-processing, and theoretically prove that the proposed scheme satisfies -differential privacy. Simulation results and analysis show that this scheme can effectively protect the user"s location privacy and make the Shared location data have good availability.