To realize high precision attitude measurement by means of astronomical observation with a camera, it is quite necessary to calibrate the parameters of the camera accurately. A camera calibration method is presented based on astronomical observation to solve the problem that the traditional calibration methods can only work effectively in a limited distance. The world coordinates of control points at the measuring time are calculated by using the spherical astronomy method. A star observation model is established according to the photogrammetric principle, both the external and intrinsic parameters of the camera are obtained, and the calibration precision is also analyzed. The experimental results indicate that the calibration method can achieve a good precision without the aid of precise and complex equipment, and the method performs also well when noise exists. Finally, the calibration result is adopted to work out the attitude of the camera, and the obtained repeatability accuracy of yaw and pitch angle is better than 10″. This method can be applied to the calibration of star sensor.