Abstract: Objective To study the status of health knowledge and behavior among young migrants,and to provide evidence and support for better health education in the population.Methods With cluster random sampling,a total of 3 034 young migrants and 1 522 local young residents aged 15-34 years were selected from Beijing,Shanghai and Shenzhen city and surveyed with a questionnaire.Results Among the young migrants,the score of health knowledge was 14.64±3.14 and the rate of health behavior was 49.11%,both of which were lower than those of local young residents; differences in the score and the rate existed among the young migrants due to variations in gender and education level(P<0.01).Young migrants acquired health knowledge mainly from newspaper/magazine/book(53.89%,1 635/3 034),broadcast/television(39.82%,1 208/3 034),and classmate/friend(39.52%,1 199/3 034)and the young migrants reported a great need for health knowledge provided by health specialists(41.23%,1 251/3 034).The results of multivariate linear regression indicated that health behavior was influenced by gender,age,education level,marital status,housing condition,and health knowledge among the young migrants(P<0.01 for all).Conclusion The average level of health knowledge was relatively low and varied in terms of the knowledge structure,with an unbalance between knowledge and behavior in young migrants.The study results suggest the needs for direct intervention on health behavior and specific health education in the population.