According to pressure vessel material waste problem in the traditional design, the finite element technique is used to pressure vessel optimization design in this paper. Firstly, the finite element analysis is applied to carry out stress calculation, and we extracted the related results parameters for following calculation. Then we conducted the quantitative calculation after choosing optimization design method, and got the best design parameters which meet performance indexes. At last, we conducted the optimization design of pressure vessels using this technology. Practical results prove the validity and the practicability of this method in the pressure vessels design.