In this paper an efficient image cryptography method by using random key (RK)-RC6 algorithm has been proposed. The implementation environment has been developed and designs in Netbeans 7.2 environment and by using Java programming language. It consists of image encryption and decryption, histogram, and information loss calculations through the entropy. The comparative images have been considered like Leena, Barbara, Cameraman, Elina etc. have been considered for the experimentation. In the RK-RC6 algorithm, the procedure of RC6 algorithm is applied along with the random key variation overlapping procedure. This overlapping procedure is developed in Java to overlap the key generated by RC6 and randomize the key in every iteration. Then we have applied XOR for the bit shuffling procedure in the image to improve the security. In this procedure different random images are used so that the bit shuffling is different in different iteration and the image security can enhance. Result shows the improved security and less information loss in case of image encryption.