In this paper, we show a validity of a new programming paradigm called constraint logic programming by constructing a robot structure design support system. The design process of a robot structure is divided into a fundamental structure design and a internal structure design. A fundamental structure design is a process that determines a framework of the robot such as a degree of freedom, a number of joint etc. We mainly support a fundamental structure design. This design system is constructed by constraint logic programming language. The buchberger algorithm is used to calculate the non linear equation in this language. Our design system generates an analysis program independent of robot structure easily. The result of analysis is also gotten in the form of expression. The constraint can be appended incrementaly. By constructing such a system we can achieve remarkable reduction of desiner's work in design process.