The KQML (knowledge query manage language) is a representative model in multi-agent interaction. In this paper, some conclusions are given about the necessary communication support to the agent-oriented program on the knowledge level based on the analysis of KQML model. Firstly, the agent statue model and the transform model of KQML communication are founded to analyze the necessary conditions in performing interaction with the synchronal and asynchronous KQML model respectively. Secondly, the deadlock and starvation problems in the communication process with the synchronal and saynchronous KQML model respectively.Secondly,the deadlock and starvation problems in the communication process with KQML model are analyzed feom the KQML stansform aspect,and the cardinal readons and the solutions are given.At last,the advantages and the disadvantages of the synchronal and asynchronous KQML model are listed respectively,and the choosing principle is given.