Abstract: The LAMOST(Large sky Area Multi-Object fibre Spectroscopic Telescope) has now come to its final completion of R&D stage. Major functions of the telescope have successfully passed a serial site tests recently, and various kinds of applications integrated into the automation of the telescope chamber is being under vigorous tests too. The TCS(Telescope Control System) is built on multi-layer distributed network platform with many sub-systems at different levels. How to efficiently process the enormous amount of message with particular implications running in and out the TCS is one of the major issues of the TCS software programming. This paper describes the mechanism and methodology of the LAMOST message bus structure. The realisation of message bus structure as a result of years of research and site test is presented in general, and dealing with the message priority and manipulating smallest piece of message in parallel or in serial sequence are elaborated in particular.