Abstract: This paper reviews the basic content of key management，points out the limitation of the existing key agreement protocol.It introduces IBE public key cryptosystems in detail and homomorphic encryption scheme in the integer ring.The homomorphism key agreement based on IBE and homomorphic encryption scheme is presented.Compared with Diffie-Hellman protocol，its operation speed is more quickly；Compared with Key Agreement protocol based on password，it has better security.The protocol can use the public key of IBE to create the contributory，forward secrecy the session key.Finally，the security of the protocol is proved by BAN logic.

摘要： 在整数环上的同态加密机制和IBE公钥密码体制基础上，提出了基于IBE的同态密钥协商。该协议建立的会话密钥是等献的、前向保密的。和Diffie-Hellman系列密钥协商协议相比，所提出的密钥协商协议具有更快的运算速度；和基于口令的密钥协商协议相比，所提出的密钥协商协议具有较好的安全性。最后利用BAN逻辑证明了该协议的安全性。