Abstract: Aiming at the strict confidentiality of coordinate transformation parameters and quasi geoid model results in urban satellite navigation and positioning continuous operation reference station (CORS) system, a general real-time encryption transformation method of urban CORS system is proposed based on bursa seven parameters and bilinear interpolation method, which realizes the real-time acquisition of plane and normal height results of urban local coordinate system This method has been verified in the application of CORS in Hefei city (HFCORS), and can provide reference for the application service of urban CORS surveying and mapping benchmark.