Mobile Social Network Site (MSNS) is introduced into teaching and learning as a kind of innovative pedagogical tool, called MSNS-based ubiquitous learning, which allows students to learn at anytime and anywhere. Continuous use is the success of an innovative tool. Nevertheless, several previous studies have indicated factors and mechanism affecting students' continuance intention in the context of MSNS-based ubiquitous learning. In this study, a behavioral model based on "cognitionaffect-conation" framework is proposed to interpret factors' impacts on students' continuance intention, along with the clarification of the mechanism. Both qualitative (focus group interview) and quantitative (survey) methods are employed in this study. Confirmatory factor analysis, hierarchical confirmatory factor analysis, and full model of structural equation modeling are applied to validate the research model and hypotheses. Results reveal that perceived convenient function, teachers' participation, interaction expansion, course content fit, and information richness are reflective constructs to the perceived quality of a MSNS-based pedagogy, which put impacts on students' continuance intention through perceived value and users' satisfaction, perceived value mediates the impact of perceived quality of an MSNS on satisfaction, and satisfaction also mediates the impact of perceived value on continuance intention.