Abstract: After near a century of research,the diverse and complicated relationship between viruses and tumors has been elucidated gradually.Last century it was demonstrated that some retroviruses and some herpes viruses could induce lymphoma and leukemia in some animals.However,it is more complicated in human.During the last two decades it has been confirmed that several types of hepatitis viruses could cause hepatocellular carcinoma and the relationship between human papillomaviruses and cervix carcinoma has been established.These viral vaccines became useful tools to prevent prevalence of these carcinomas.Because of the successful inoculation of live attenuated viral vaccines all around the world in recent 15 years,oncolytic virotherapy is revived,and provides a novel strategy for treatment of refractory tumors.