A Location Based Service (LBS) is an information, entertainment and utility service generally accessible by mobile devices such as, mobile phones, GPS devices, pocket PCs, and operates through a mobile network. Location-Based Service (LBS) is booming up in recent years with the rapid growth of mobile devices and the emerging of cloud computing paradigm. Along with the challenges to establish LBS and the user privacy issue becomes the most important concern. So successful privacy-preserving LBS must be secure and provide accurate query results. In this paper, the authors present a solution to one of the location-based query problems.