Aim at the current situation of high energy-consumption of the large public building，proposed a WebAccess–based energy-consumption management and energy-saving analysis system.And it be used Zigbee distributed energy consumption measurement net for data remote transmission. The status of energy consumption in the future can be predicted through energy-consumption databases and energy-consumption models were built. The system can real time monitor and manage the energy-consumption status in large public constructions. It can provide a favorable foundation not only for energy conservation and reformation of those completed large public building, but also for energy conserved operation and supervision of those new constructions. This can help to achieve the goal of energy conservation and energy-consumption reduction in large public building.