Abstract: We present the principals for BDS and BDS/GPS real-time kinematic (RTK) positioning. A experiment was conducted on Songshan calibration field using a UAV-based low altitude photograph platform which carried a double frequency GNSS system simultaneously receiving BDS and GPS signals. By comparing the positioning result of GPS, BDS, and the BDS/GPS-combined RTK models, and using these three groups of camera exposure station coordinates to carry out GNSS-supported aerotriangulation. These experiments demonstrate that the performance of GPS, BDS and BDS/GPS-combined RTK positioning model are very close in bundle block adjustment. For all three groups, the overall root mean square error was all lower than±0.17 m for the planimetry and±0.25 m for height, which satisfies the Chinese National specifications of aerial photogrammetric 1:500 mapping in hilly regions.