A novel method for computer-generated rainbow hologram of full-color objects is proposed in this paper. Firstly, a new algorithm for fabricating full-color computer-generated rainbow hologram (CGRH) of real-existing objects is proposed based on the interrelationship between coding of CGRH and reconstruction of hologram. Secondly, a color rainbow hologram for real-existing object is generated by combining the proposed algorithm and computer-generated holograms (CGHS) generating system. Finally, the hologram is output by an auto-microfilming system. The principle of the algorithm, process of hologram calculation, hologram generating system for real-existing objects and experimental results are presented. The experimental results demonstrate the new method is feasible.