Abstract: Objective To examine smoking behavior and to explore the psychosocial factors associated with smoking among adolescents in Yanqing county,Beijing city.Methods Totally 1 466 students from 5 middle schools or vocational schools in Yanqing county were randomly selected for a anonymous questionnaire survey.Results The reported rate of attempting to smoke was 32.9% and the current smoking rate was 12.3%,with a reported ever-smoking rate of 6.5%.The smoking rate of the males was higher than that of the females and the smoking rate of vocational students was higher than those of middle and high school students.For the students with an attempt to smoke,50.1% had the first smoking before the age of 12 years and 59.4% tried to smoke because of curiousness.Among the middle school students with smoking behavior,62.1% had smoked with their classmates or friends.There were 56.3% of the students reporting cigarette purchase around the schools.Multivariate logistic regrssion analyses showed that the risk factors of smoking were studying in vocational school,male gender,smoking behaviror of the peers,the eagerness to imitate smoking activity of the performers in film or TV program,with mental health problem,and with poor study archievement;the protective factors for attempt to smoke were with correct attitude to smoking and the restriction on smoking at home.Conclusion The smoking behavior among adolescents in Yangqing county is prevalent and specific intervention should be conducted as soon as possible.