As a typical algorithm for star identification, grid algorithm has advantage of fast identification time, high identification rate and small capacity of guide star database, but it has the problem of rotating the picture with a chosen neighbor-star when creating the star pattern. In order to solve the problem, a star identification algorithm based on rotation-invariant is proposed. The algorithm uses the star identification algorithm based on idea of pattern-recognition to build a rotation independence pattern for every star, and uses the improved Hausdorff distance for the matching. The simulation results show that identification algorithm based on the rotation-invariant based star has a better robustness in position errors and lost stars than grid algorithm, and the algorithm has good recognition effect, but the identification time and memory capacity still need to be optimized.