The purposes of this study were to explore college students' perceptions, uses of, and motivations for using Wikipedia, and to understand their information behavior concerning Wikipedia based on social cognitive theory (SCT). A Web survey was used to collect data in the spring of 2008. The study sample consisted of students from an introductory undergraduate course at a large public university in the midwestern United States. A total of 134 students participated in the study, resulting in a 32.8% response rate. The major findings of the study include the following: Approximately one-third of the students reported using Wikipedia for academic purposes. The students tended to use Wikipedia for quickly checking facts and finding background information. They had positive past experiences with Wikipedia; however, interestingly, their perceptions of its information quality were not correspondingly high. The level of their confidence in evaluating Wikipedia's information quality was, at most, moderate. Respondents' past experience with Wikipedia, their positive emotional state, their disposition to believe information in Wikipedia, and information utility were positively related to their outcome expectations of Wikipedia. However, among the factors affecting outcome expectations, only information utility and respondents' positive emotions toward Wikipedia were related to their use of it. Further, when all of the independent variables, including the mediator, outcome expectations, were considered, only the variable information utility was related to Wikipedia use, which may imply a limited applicability of SCT to understanding Wikipedia use. However, more empirical evidence is needed to determine the applicability of this theory to Wikipedia use. Finally, this study supports the knowledge value of Wikipedia (Fallis, 2008), despite students' cautious attitudes toward Wikipedia. The study suggests that educators and librarians need to provide better guidelines for using Wikipedia, rather than prohibiting Wikipedia use altogether.