Abstract: An implementation scheme to realize BAS (building automation system) energy-saving control in metro ISCS (integrated supervisory control system) is introduced. In this scheme, the enthalpy control operation, the frequency control and speed regulation of fan, the automatic adjustment of two-way valve opening and other adaptive control algorithms are integrated by ISCS platform. The enthalpy mode, fan frequency and two-way valve opening are automatically issued according to the periodic calculation results, thus the goal of reducing energy consumption and providing high quality riding environment for passengers is achieved.