Aiming at the problems of difficult parameter transfer, poor relevance and high requirements for designers in the process of parametric design of agricultural machinery models, a set of interactive creation system for model parametric design was constructed. The system used the concept of knowledge element design to create design knowledge through a man-machine interactive method to realize the personalized design and parametric modeling of the model. Combining the secondary development technology of SolidWorks and MySQL database management to realize the resource encapsulation of model parametric design, in order to weaken the limitation of professional background knowledge. Taking the grain harvester cutting device as the test object, the parameter relationship between the parts was analyzed, the parameter design rules were clarified, the design parameters were marked through the model preprocessing, and the model data set was looped to extract the basic information of the parameters, a human-computer interaction interface was established, and following the classification requirement of parameters, the quantitative and qualitative knowledge and information expression of design parameters were completed. The case analysis proved the feasibility and effectiveness of the system，and it was easy to understand and apply. At the same time, it can also provide technical support for the design and reuse technology of agricultural machinery and equipment.