Based on suming up newest accomplishment of automotive CAD technology inside the country and abroad, B-spline mathematics method has been used and automotive body surface mathematics model has been founded up in the article. Furthemore, applicable automotive body geometrcal modelling ABGD system has been designed by means of algorithm and program. ABGD system was written by stamdard FORTRAN 77 language of computer by help of PLOT 10 GKS standard graphic software and is operated on the VAX seriesmain computer. The system can be linked with 3-coordinate measurment machine controlledby computer. There are plentiful interactive functions in the system. Practical check shows that the system is operated reliably and possesses satisfactory design results.