Team-Based Learning (TBL) has been widely applied in different fields (courses) and has been indicated to be efficient. Meanwhile, many studies have asserted that Group awareness (GA) information, which visually displays peers' learning context and activities, can increase peer participation within an online collaborative learning environment. As the level of preparation by students before class affects their subsequent learning performance in the TBL process, this study incorporates GA information into the preparation stage of TBL process and further develops the online TBL + GA system in order to raise peer preparation level. Furthermore, self-regulated learning (SRL) levels of a student and online learning environment interactively influence learning effectiveness. Accordingly, this study further investigates how the TBL + GA environment influences students with different SRL levels. Two freshman classes were randomly chosen, with one as the control class (using the traditional TBL) and the other as the experimental class using the TBL + GA. Analytical results indicate that although the two classes do not reach significance overall on preparation level, TBL + GA can significantly enhance preparation levels for high-SRL students, but not low-SRL students.