This paper presents a distributed multi-agent dynamic cooperation method. In the system, the communication between agents has some special requirements. One of them is asynchronous communication. Communication sequence process (CSP) is used to descript a model of agents’ communication with shared buffer channel. The essence of this model is very suitable for the multi-agents communication, so it is the base for our next step job. Based on the communication model, the figure of agents’ organization is given by exploring the distributed tasks dealing method among joint intention agents and with description of relation between tasks. Agents communicate with each other in this kind of organization. The semantics of agent communication is another emphasis in this paper. With the detailed description of agents’ communication process, given a general agent automated negotiation protocol based on speech act theory in MAS, then we use CSP to verify that this protocol has properties of safety and aliveness. So it is proved it is logic right. At last a frame of this protocol’s realization was given.