Abstract: According to the need of application of digital manufacturing in workshop, a computer simulation modeling technology of weld forming process based on Bezier curve is presented in this paper. The mapping relationship between the welding parameters and the geometrical features of the weld is established by analyzing the regularity of welds in arc welding. The B-rep method is used to study the geometric feature modeling technology of welds in arc welding , and OpenGL technology is used to develop computer simulation prototype of weld forming. The results of the simulation show that the modeling technology of weld forming process and computer simulation system presented in the paper can guide the digital design of the welding process effectively.