Abstract: With the developments of network communication, electronic commerce plays a more and more role in the trade business and industry structure. The requirement for the electronic commerce turns to be higher. In this study, we study current status about the cryptographic algorithms exploited in electronic commerce. We discuss the advantages and disadvantages about the symmetric and asymmetric algorithms and improve them. Then we give a new scheme that combines the improved symmetric algorithm and asymmetric algorithm. We give sound reasons to explain why our scheme is more secure. Finally, we carry the experiments to show the security of our scheme