Confidentiality is one of the most nontrivial issues in secrecy of group communication. In order to satisfy confidentiality, symmetric cryptography must be exploited. All symmetric algorithms require a shared key between the members of group. High frequency in the number of joins and leaves of members can cause huge number of messages of data between authorized group members. Although hierarchical group communication is a prominent model, it has not been investigated in security literature as well as other models. There has been an extensive research on satisfying confidentiality in group communications on different architecture other than the hierarchical architecture and the proposed hierarchical models do not use the concept of agents. A concept that brings its own advantages. In this paper, we investigate a new approach to secure key management in hierarchical group communication by means of using intelligent agents. The simulation results show that using agents reduce network bandwidth and improve and achieve more performance comparing with other models. Moreover, using agents makes the architecture more flexible and dynamic preparing it for Grid Computing technologies.