Abstract: Objective To investigate the knowledge of acquired immunodeficiency syndrome(AIDS)of migrant workers working outside.Methods 791 migrant workers were chosen by random sampling method.They were surveyed by using questionnaire about AIDS.Results 61.2% workers thought that HIV virus can be transmitted by mosquito and insect.Only 27.4% people were willing to be friends with AIDS patients.The rate of accurate learning for the 3 transmission routes of AIDS was higher.However few interviewees knew the ways by which the disease was not transmission.Univariate analysis showed that influence factors of score of awareness were education,hometown,marital status and income.Multiple linear step regression analysis showed that factors of influencing scores of awareness were age,education,hometown and income.Analysis showed that the main influence factor of transmission routes score of awareness was education.Conclusion Education to migrant workers is a bottleneck problem in society.Health education of A IDS for high-risk people,such as migrant workers,is important to AIDS prevention.