Objective:To investigate whether apoptin is a apoptosis-inducing protein with a potential for bladder cancertherapy. Methods: We constructed a PCDNA3/Apoptin eukaryotic expression vector, and transfected this vectorinto bladder cancer cell lines BIU-87 and EJ, then observed the results by RT-PCR, transmission electronmicroscopy, MTT assay and the flow cytometry (TUNEL method). Results: PCDNA3/Apoptin successfullyinduced a high level apoptosis in both bladder cancer cell lines, compared with the controls (p<0.05). Conclusions:Apoptin can induce high level apoptosis in human bladder cancer EJ and BIU-87 cells, which suggests a potentialfor human bladder cancer therapy.