User-Generated Content (UGC) such as online travel reviews written by travelers and posted to virtual communities are being used more frequently to communicate travel-related information. UGC is therefore helping travelers to make decisions about their travel. Utilizing the Theory of Planned Behavior (TPB), which is one of the most comprehensive models explaining behavioral intention, this study contributes to the further development of theories of online consumer behavior by determining which factors are most important in relation to the use of UGC in the travel industry. The TPB has three independent determinants of behavioral intention: attitude toward the behavior, subjective norm, and perceived behavior control. Therefore the aim of this paper is to examine the roles of attitude, subjective norm and perceived behavior control in respect of travelers’ intention to use UGC when making travel plans.