In order to represent complex graph drawing in the course of 3-dimensional dynamic simulating flexible objects such as fabric、garment、rope、netting yarn and rubber band, we designed a new mathematic model named operator cube. Any graph formed on the basis of the point information. In a word, if each point has enough geometry information, the graph can be drawn and rendered. Operator cube model came into being just because of that idea. The paper mainly discussed the theory of operator cube model. The model can transform a complex graph into a simple representation effectively and in real time, especially in the course of topology structure varying flexible object simulation. What’s more, the model can accurately express the simulation results. The model converted between the world coordinate system space and device coordinate system space. And the model and the conversion involved some profound mathematic theorems and our conclusions which were proved strictly.