Cytoplasmic transduction peptide (CTP) is a newly designed transduction peptide, by which special molecules can be carried out and localized into cytoplasmic compartment. Superoxide dismutase (SOD) is a protein that is difficult to go into cytoplasm. In this study, CTP-SOD fusion gene was amplified from human cDNA by PCR, and the active recombinant protein was successfully expressed in Pichia pastoris. HeLa cells pretreated with CTP-SOD showed a significantly improved survival against the pyrogallol-induced oxidative stress, suggesting CTP-SOD could cross the cell membrane more efficiently and protect cells from oxidative stress.