In this paper, the authors present a security visiting guiding system SVG composed of RFID, smart phone, and Wi-Fi signal widely available. The SVG system can provide visitors with the map of a given building, so that the visitor can easily find the target under its guide. It can also protect user's privacy location information by cryptographic two-dimension code and RFID. The two-dimension code can be easily obtained by a mobile phone and it authorizes a visitor to obtain the navigation service of SVG. The visitor receives the permission from his host and makes a date through SVG.