Abstract: In order to improve the pre-processing efficiency of massive aircraft CAD models,a parallel processing system based on PC-cluster instead of a single PC is constructed by using the message passing interface(MPI).With the parts and components from the CAD model assembly tree as objects,a parallel pre-processing algorithm is presented.By simplifying the geometrical models,generating LOD and partitioning the models in a parallel way,meanwhile,balancing the dynamic load and optimizing the data transmission and storage,the pre-processing efficiency can be improved drastically.An example,in which the aircraft CAD models with ten millions of triangles and storage up to GB level can be processed in 60 seconds,is given to demonstrate the efficiency of this approach.The experimental result shows that the processing speed with the method can be improved more than 10 times over that with the single PC.