Abstract: Under the Windows 2000 operation system,using the Visual Basic 6.0 program design environment,expert system for supervision quality control of building construction is developed.The system consists of knowledge base,inference engine,explanation facility,user interface,knowledge acquisition facility,dynamic database.It can diagnose quantity limitation(accident) of building construction in construction period,and commentate the reasons,measures of prevent and disposal of the quantity limitation(accident).The user also can seek information about quality control of building construction in construction period(quality standards,quality control point,quality control flow,quality of building material and building machinery,laws and regulations and so on).This system is open to any user for modifying and adding information expediently.