Nowadays, team learning and blended learning are becoming increasingly important to today's university students. Knowledge sharing (KS), as an important factor that is the bridge between learning and cooperation and communication, can affect the effectiveness of students' learning. However, current research has paid less attention to knowledge-sharing behavior (KSB) under blended team-based learning (BTBL). This paper explored the factors that influence KSB in BTBL, 322 samples were analyzed using the partial least squares structural equation model (PLS-SEM). The results showed that team atmosphere, reciprocity, sharing attitude, and knowledge self-efficacy (KSE) had significant positive effects on KSB. Meanwhile, team learning ability (TLA) significantly negatively moderated sharing attitude and significantly positively moderated KSE.