Abstract: Objective: To investigate the possibility of using rhHSP70 obtained from the gene-modified Pichia pas-toris and complexed with the CTL epitopes to cure cancer. Methods: We constructed rhHSP70-HER2/neu peptides com-plexes in vitro and immunized BALB/c mice with breast cancer, then assayed the specific CTL induced by the complexesthrough ELISPOT and Granzyme releaseing method. At the same time, we observed the tumor volume and the histology ofthe tumors to analyze the remedial effect of the complexes. Results: The rhHSP70-HER2/neu peptide complexes couldenhance T cells to secret IFN-γ, induce specific CTL and had obvious remedial effect on mice with breast cancer. Conclusion: rhHSP70 produced by Pichia pastoris can bind some polypeptides in vitro and the subsequent rhHSP70-peptidecomplexes have therapeutic effects on mice with breast cancer.