Purpose - This study analyzed the characteristics of social networking sites (SNSs) using related literatures, and researched the models discussed in precedent studies, to investigate the effects of SNS characteristics upon consumers'awareness, purchase intention, and recommendation. The purpose of the study was to investigate the use of SNSs as a marketing tool. Design, methodology, and approach - For an empirical analysis, the author distributed questionnaires online and offline, to verify the models and hypotheses. Respondents were persons aged 17 or older, who were frequent users of SNSs. The questionnaire survey was conducted for 11 days from September 30, 2013 to October 10, 2013. The author distributed 450 copies and received 430 responses. Finally, 412 copies were used for the analysis after excluding 18 copies having poor answers. Results - The findings about SNS users' behavior could be used as material in the future use of SNS as a marketing tool. Further, the study provided not only theories about SNS characteristics, but also variables and items that were verified during the empirical study. Conclusions - Further studies are needed to overcome the limitations and to establish various kinds of SNS marketing strategies in detail.