Heavy metal resistance microorganism plays an important role on polluted soil bioremediation. To obtain further knowledge of the resistant mechanism employed by cadmium-resistant bacteria, some gene expression profiles at transcription level were investigated in P. aeruginosa E(1) subjected to cadmium stress using real-time PCR. Exposure to cadmium for 1 h, the expression of czcA, czcB, and czcC all reached the peak of up-regulation 8.82-, 4.83-, and 7.43-fold, respectively. The response of czcD was earlier and stronger than czcABC. CysM contributed to cysteine synthesis kept up-regulation within the beginning 2 h. The expression of mgtAE genes related to Mg(2+) influx was up-regulated all the while, znuB responsible for Zn(2+) transportation kept up-regulation from 30 min to 4 h. The result support the two cadmium-resistance mechanisms including effluxing and inactive the heavy metal ions. The mechanism was brought that increase of Mg(2+) and Zn(2+) in cytoplasm would prevent Cd(2+)-binding enzymes to decrease the harm to cell.