Abstract: In recent years, the design method of moldboard plough surface has been developing from empirical design method toward mathmatical & analytical describing and designing method. It is undoubted that the uniting of agrotechnical demand with moldboard plough surface parameters in design procedures has become the future trend to design plough surface. By means of computer application, this paper studied and investigated outline formation principle and method of moldboard plough surface, related agrotechnical requirement of tillage quality with outline design parameters, and finally established quantitative relations between suitable moldboard plough outline shape and various agronomical demands, mathmatical models of moldboard plough surface & design parameters.