Abstract: In recent years,video conference system has rapidly developed and been applied in various industry.Yunnan meteorological department is a typical representation.The perfect video conference system has been built from central department to county department.The system makes full use of the current advanced multimedia technology,automatic control technology and network communication technology.It is a huge system which is composed of many subsystems and lots of various equipments.And it has complex structure and powerful function.As an example,this paper analyzes the constitution of current common video conference system,especially describing the overall architecture and some key parts such as video conference terminal,multipoint control unit,large screen montage subsystem,centralized control subsystem.