This semester-long qualitative case study, spanning 4 months, focused on an English reading course in which 20 university English-as-a-foreign-language readers were instructed to engage in web-based collaborative learning outside of class. The study drew on data resources including interviews with students, field notes on their web-based collaborative learning practices, and students’ written reflections. A thematic analysis of the data sources shows that the positivity of student readers’ beliefs about web-based collaborative learning (i.e., about web-based collaborative platforms and reading activities) changed over time but ultimately became stably positive. The change was found to be related to the interactions between their beliefs about web-based collaborative platforms and their beliefs about reading activities over time. The students’ beliefs about web-based collaborative learning were also found to be sensitive to factors regarding the students’ learning over time, including their prior learning experiences and their ongoing learning experiences. In the process, the students’ web-based collaborative learning practices were primarily driven by their positive beliefs and constrained by their negative beliefs although additional factors emerged over time from their learning process and intervened in the relationship between their beliefs and their learning. The implications of these findings on how to best engage students in web-based learning are discussed.