The number of distributed components and devices never?cease to increase. As a result, distributed control methods are neces-?sary in order to manage and utilize these devices. Over the past few?years agent based technology becomes an eective tool for engineering?applications. As a computational paradigm, Multi Agent System (MAS)?appears to be an answer to satisfy the requirement of intelligence in a?distributed system. This paradigm also accepts networking and distri-bution as a basic concept. MAS is a set a agent, situated in a common?environment that can act interact each other autonomously with intel-ligent behavior and can solve complex problem. Mobility is property of?agent which allows him to migrate from one host to another to achievetheir goal.Researchers in dierent area have been attracted by systems?based on Mobile Agent (MA), because of their pro-active aspects and?their autonomous tasks.Unfortunately, security of mobile agents is very?complicated especially when it comes to secure an entity that migrates?from one platform to another across the network, and which must be?executed correctly and safely on the hosting platform. In this paper we'll?focus on the security aspect of a mobile agent from one platform to?another, by introducing a new approach based on cryptographic mech-anisms to get a session key, to guarantee a mutual authentication and?the condentiality of data exchanged, as well as a binary serialization to?ensure the mobility of the agent across the network.