This study aims at exploring factors influencing continuance intention to use mobile social networking sites (SNS). Specifically, this study attempts to investigate the effects of stress and regret. [Method /process] 226 valid data from working stuff were collected via questionnaires and further analyzed using SEM. [Result /conclusion] Results show that, stress and regret have significant impacts on continuance intention to use mobile SNS. Also, technology-work conflict and technology-personal conflict have significant influences on stress, and excessive use has a significant effect on regret.