Abstract: Objective: To investigate the experimental value of HSV -TK/ACV transfected by cationic liposome to treat human lung cancer cell. Methods： With the cationic lipofectAMINE, we transfect the eukaryotic expressing liposome pCR3-TK, which was constructed before, to human lung cancer cell line Anip973, and then different concentration Aciclovir (ACV) was administrated. Results: MTT confirmed the increasing sensitivity level of TK gene-transfected lung cancer cells to ACV. FCM showed apoptosis and S phase blocking had occurred in the cell lines transfected with pCR3 -TK. Conclusion: The results indicate that HSV-TK/ACV system is a promising gene therapy approach for the human lung cancer cell line Anip973 and the cationic liposome is a safe vector for gene transfection.