Recently, the rapid growth of users has considered ending their Facebook use or actually done so due to privacy issues, concerns about overexposing personal information online, or interpersonal interventions or distress. This study conducted research on users of Facebook, the most representative social networking site in the world, to determine the effect of Big Five personality traits, self-monitoring, and Facebook usage behaviors on continuance usage intention. A total of 498 valid samples were collected from a questionnaire survey and a multivariate nonparametric regression technique -multivariate adaptive regression splines-was employed to screen critical variables and predict users' continuance usage intention in the future. The results revealed that when the main motivation for Facebook use is not documenting life or expressing emotions, continuance usage intention notably decreases. In addition, the degree of agreeableness has a moderating effect on the relationship between Facebook usage behaviors and continuance usage intention.