Previous studies and reports of drug abuse cases in China indicate that college students' perceptions and attitudes toward illegal drugs may have been greatly impacted by the changing social surroundings. However, little work has been done to assess empirically their willingness and perceptions of using drugs. This paper, therefore, focuses on examining the intention of college students' drug using and its influential factors. It draws upon the framework of the theory of planned behavior (TPB) which contains three constructs to predict intentions of a certain behavior, namely attitude, social norm and perceived control. Additionally, it explored whether prevention education may exert an influence on drug use intention. A survey was conducted among college students from 20 universities in Beijing with a self-report questionnaire. A total of 1,425 valid questionnaires were collected. The results show that only 2.3% of the respondents reported they had intentions of using illegal drugs. Other main findings include that attitudes (measured by knowledge on drugs and harm perception) is a significant protective factor of college students' drug use intention, while social norms (measured by invitation of others) and perceived control (weighted by visibility of drugs on campus) are the risk factors. The usability of the TPB has been generally testified in this paper, whereas the result on several items showed different feedbacks than prior studies. The study reveals significant correlations between drug use intention and prevention programs of specific organizers and forms. Based on these findings, possible explanations and policy recommendations are provided.