Abstract: A visual automatic test environment (CAT-VATE) based on the technique of flow design is discussed as well as the research work.The object-oriented design (OOD) method is adopted to design the visual objects of test software and the technique of virtual instrument is used to implement the instrument driver software in the CAT-VATE.Based on these techniques, the flow design of CAT-VATE can be achieved with the mechanism of control data flow.Some features and the architecture of CAT-VATE are illustrated with an experiment.