Objectives To investigate the influenza vaccination rate of children under 5 years old in 10 outpatient vaccination clinics in Binzhou City of Shandong Province from 2015 to 2017,and to analyze the influencing factors,in order to provide data for the influenza vaccination. Methods A total of 480 parents of children under 5 years old in Binzhou were investigated by self-made questionnaire and analyzed retrospectively.The influencing factors of influenza vaccination among children under 5 years old were analyzed by Logistic regression model. Results Influenza vaccination rate of children under 5 years old in 10 vaccination clinics in Binzhou City decreased from 42.29% (203/480) in 2015 to 20.21% (97/480) in 2017,among which the vaccination rate of children aged 3 to 5 years old decreased from 26.87% (129/480) in 2015 to 13.13% (63/480) in 2017,and the vaccination rate of infants under 3 years old decreased from 15.42% (74/480) in 2015 to 7.08% (34/480) in 2017,with significant downward trends (χ²=11.073,14.312,P< 0.05).Parents with educational level higher than middle school (senior high school/secondary vocational college/higher vocational college OR=1.49,95% CI: 1.08-2.04;undergraduate/college OR=2.45,95% CI: 1.61-3.73;master degree or above OR=3.90,95% CI: 1.70-8.87),family monthly per capita income higher than 3 000 yuan (3 000-5 999 yuan OR=1.35,95% CI: 1.07-1.71;≥6 000 yuan OR=2.37,95% CI: 1.25-4.51),employees of government,enterprises and institutions (OR=3.15,95% CI: 1.71-5.80)and having knowledge on influenza vaccine(OR=2.24,95%CI:1.56-3.21) were factors which can promote the vaccine coverage rate in children. Conclusions Education level,family income and knowledge on influenza vaccine are the important factors affecting the influenza vaccination rate of infants and young children.Thus,it is suggested to conduct health education on influenza vaccination.