This study explores how group dynamics (such as group cohesiveness and group norms) influence learners ’willingness to communicate (WTC) in an EFL classroom. The results from the 236 questionnaires showed that there was a significant correla-tion between group dynamics and WTC in an EFL classroom. A dozen students who participated in this study were interviewed for more in-depth information and the data revealed that most interviewees acknowledged the importance of the class group. The qualitative data also showed the importance of their own determination to learn in establishing their WTC.