Component Based Software Engineering (CBSE) is an excellent candidate to achieve greater software understanding, reuse and reliability. In this paper, we presented how this paradigm could be applied in the development of system from an alternative way. In this way, that is, to imitate the way of circuit board assembly process, we brought forward the concept of soft-board and further, the soft-board based method to develop system. In particular, by taking Auto Test System (ATS) for example, we designed the general structure of soft-board which is extensible and provides the fundamental framework-the infrastructure and service, to construct system. Then the controller component, which is the key component of soft-board, was designed based on the technology of component object model (COM). At last, the system development process based on soft-board was given.