The purpose of this study is to investigate whether online social presence exhibits itself differently in Chinese culture and American culture. Specifically, a multiple-group confirmatory factor analysis (MCFA) of the Computer-Mediated Communication Questionnaire (CMCQ) scores collected from college students in Taiwan and America will be conducted to assess the equality of the online social presence construct across two cultures. The CMCQ has been developed and revised to measure the construct of online social presence (Tu, 2002; Tu & Yen, 2006a; Tu & Yen, 2006b; Yen & Tu, 2008). Online social presence is the degrees of feeling, perception, and reaction of being connected by computer-mediated communication (CMC) to another intellectual entity through electronic media (Tu & McIsaac, 2002) and found to influence the outcomes in online learning (Gunawardena & McIsaac, 2003). As suggested by past research, higher teacher social presence tended to be accompanied by higher quality of knowledge acquisition on the student’s part (Weidenmann, Paechter & Schweizer, 2000). Additionally, a high degree of social presence would initiate and maintain more and deeper interactions in learning (Polhemus, Shih & Swan, 2001). On the contrary, the lack of social presence was accompanied by the students’ experiences of frustration, more critical attitude of the instructor's effectiveness (Rifkind, 1992), and lower level of affective learning (Hample & Dallinger, 1995). Students in differ cultures may vary in their perceptions of the computer-mediated communication (CMC) learning environments and, in turn, the meaning of online social presence may change across cultures. Therefore, the generalizability of the factor structure of online social presence to college students in Chinese culture and American culture needs to be empirically assessed.