Nasopharyngeal carcinoma (NPC) is an important cancer in Southern China and Southeast Asia, with a high incidence of over 20 per ten million and 15,000 new patients each year.P 16 is one of the tumor depressor genes associated with NPC with over 60% deletion or inactivation in NPC cells.In this study, a recombinant P 16-adenovirus (rAd-P 16) was constructed by using a third generation adenovirus vector and the AdMax delivery and expression system, and packaged into the (293HI-IQ) cell line.In vitro study showed that the P16 gene has high levels of mRNA and protein expression in NPC cells after infected with rAd-P16, and that the rAd-P16 can efficiently limit the growth of NPC cells with a significant decline of cell viability, down to 20% using 25 MOI of rAd-P16 in NPC cell lines such as CNE-1,HNE-1,HONE-1.The rAd-P16 gene therapy resulted in mainly apoptosis of the NPC cells as indicated by flow cytometry.