The Primary Purpose of this study is to identify the determinants of the users' satisfaction and continuance use intention in SNS. This study has identified three dimensions in the concept of perceived interactivity, such as user control, two-way communication, and responsiveness, and four dimensions in the concept of perceived risk, such as privacy risk, social risk, psychological risk, and time loss risk. A total 355 usable survey responses of SNS users have been employed in the analysis. The major findings from the data analyses are as follows. Firstly, perceived interactivity had a positive influence upon perceived usefulness, perceived playfulness, and satisfaction. Secondly, perceived risk had a significant influence upon perceived playfulness, however, perceived risk had not a significant influence upon perceived usefulness and satisfaction. Thirdly, perceived usefulness and playfulness had a positive influence upon satisfaction. Lastly, perceived usefulness, satisfaction, and perceived playfulness had a positive relationship to continuance use intention. Based on these results, managerial and theoretical implications are discussed, and further research issues are suggested.