Radial-Hartmann wave-front Test System(RHTS)is a new measurement system for large-aperture optical system. It can be used for the measurement of the optical system without a large-flat mirror in the room. Currently, this system has some problems such as long time for measurement, large mount of image acquisition and the instability of the surrounding environment such as temperature and noise. During the course of the measurement for large-aperture optical system, based on the analysis of the control flow, a control method for dynamic measuring is put forward, a control circuit for the dynamic measuring is designed. And a fast dynamic measurement of the RHTS is achieved and the test time is decreased with a new method of data collection and calculation.