The purpose of this study is to investigate the influence of determinants of Smartphone purchasing such as A/S, brand, H/W, switching cost, design on customer satisfaction and verify the accordance of the results of existing researches and our research with customers’ actual experience. The study also sought to confirm if moderating effects exist between determinants of Smartphone purchasing and customer satisfaction by age, gender. Data for this study was gathered by analyzing the results of a survey we conducted on 252 respondents. By taking into account the results of antecedent researches, we determined A/S, brand, H/W, switching cost, design as the 5 main factors that influence Smartphone purchasing behavior. We focused on analyzing the effect determinants of Smartphone purchasing has on consumer satisfaction and whether there exist any moderating effects between the determinants of Smartphone purchasing and consumer satisfaction by age and gender. As a result, we found out that design, brand, H/W had a significant influence on consumer satisfaction in the descending order. Switching cost and A/S turned out to have very little influence on consumer satisfaction. Also as a result of analyzing the moderating effects between determinants of Smartphone purchasing and consumer satisfaction by age and gender, the study verified that that A/S had the most significant influence as a moderating effect on age. And as for gender, switching cost was turned out to have a significant influence. The result of this study indicates several academic and practical implications for customer satisfaction of Smartphone business. Therefore, this result is expected to contribute to verifying influential factors of customer satisfaction improvement both academically and practically.