Abstract: A real time analysis system has been developed on the basis of a measuring and control system made by ANACON company. This paper introduces the sampling way of exhaust, structure of hardware and software. We choose a kind of graphic language “labview” to develop the software. This system is based on virtual instrument technologies. It mainly consists of the module of driving, data acquiring, calibrating, monitoring, span setting rang setting information base, analyzing, printing and main controlling. Which can be called each other. The function of consecutive exhaust sampling, real time data acquisition and analysis has been added. The system has been applied to the test of the three way catalytic converter and the development of the PLG vehicle.