An exterior attitude calculation method by taking Rodrigues parmeter as the attitute representation parameter was presented to overcome the shortcomings of the constraints and complexity of traditional attitude calculation algorithms and to increase the real-time performance for the multi-linear CCD spatial object exterior attitude measurement system.A multi-linear CCD exterior attitude calculation model was deduced based on the high efficiency of the Rodrigues parameter and the relationship of the intersection vector between the line segments composed of point cooperation targets. In order to avoid the singularity in attitude calculation, a switching theory of the Rodrigues parameters is combined in the algorithm and the process of this attitude calculation method was also given. Experimental results indicate that the computational-complexity of the proposed algorithm is reduced by 37.6% as compared with that of the quaternion method on the premise of assuring precision, and it is superior to quaternion method in real-time performance. At the same time, it avoids the singularity problem.