The application of digital simulation to analysis of dynamic system, such as control systems or physical phenomena, has been increasing, and the application-oriented language such as CSMP (Continuous System Modelling Program) or CSPL (Continuous System Program Language) has been developed so far. However, these languages are implemented on large-scale computers, but not on small-scale ones. Today, a small computer, with the CRT display, the floppy disk and the printer, has become popular, and its cost performance is excellent. Hence, the author has developed a micro computer-based continuous system simulation program (MCSP). This program is written in BASIC and provides an applidation-oriented language that allows models to be prepared directly and simply eithear from a set of ordinary differential equations. This paper describes the constitution of this language, application to control system design, calculation speed and errors.