Abstract: Superplastic bulging of duralumin LY12CZ under a strong electric field,without any pretreatment,is investigated. The experimental results show that: the relative limit height of the superplastic bulging increases by 15% with the strong electric field. It results from the improved superplasticity of duralumin LY12CZ during the superplastic bulging with a strong electric field,according to the measurement results of the dimensions and the equiaxed ratio of the grain size and the observation results of the cavities. Meanwhile,the practicability of a strong electric field applied to the superplastic forming of metallic materials is also verified.