Objective To evaluate the effect of influenza vaccination among senior citizens. Method 670 retired staffs received influenza vaccination as the inoculation group

and 675 retired staff did not receive influenza vaccination as the non-inoculation group. Investigation with questionnaires uas wndertaken in the two groups 3 months after vaccination.The incidence rates and treatment courses between the two groups were compared.Results The incidence rate of flu syndrome in the observation group and the control group were 11.2% and 23.7%respectively（P<0.01）

the vaccine’s protective rate was 52.74%.The ratio of patients with one kind of drug medication was 66.7% in the observation group and 25.0% in the control group（P<0.01）;two or more kinds of drug medicatior

33.3% vs. 75.0%（P<0.01）The differences are statistically significant. Conclusion Influenza vaccination exerted protective effect on senior citizens.