Abstract: Aerial triangulation, assisted by differential GNSS, is essential part of precise positioning of UAV image elements. As the sampling frequency of GNSS module usually does not exceed 50Hz, higher sampling frequency would be a serious problem for software and hardware of UAV. In this paper, 3D-coordinate interpolation for high dynamic positioning of UAV is realized based on cubic spline interpolation approach, whose applicability has been tested by real measurements. The experimental results show that clamped spline is more suitable for high dynamic interpolation of UAV. When the sampling frequency is higher than 5 Hz, plane interpolation accuracy is better than 1 cm and elevation interpolation is better than 2.2 cm.