Abstract: Objective To observe the immune effect and safety of influenza vaccine.Methods These 192 children aged between 7-9 years old in Hangzhou were vaccinated from Jun.to Fed of 1999 and evaluated their immunity level before and after vaccination.Results The result showed that positive seroconversion rates of anti-H₁N₁,anti-H₃N₂ and anti-HI were raised respectively from 1.56%,;53.13% and 53.60% to 82.81%.87.50% and 97.92%;and antibody density increased respectively 18.9,2.9 and 5.79 times of seroconversion density before vaccination.The side-effect rates was 1.6%.Conclusion The study showed that influenza vaccine were worthy of popularization for its good immune effect and safety.