Purpose <p>This study aims to elucidate the longitudinal mechanisms linking perceived teacher expectations to college students’ academic engagement, specifically by examining the sequential mechanisms through basic psychological need satisfaction and teacher credibility, and investigating how academic stress contextualizes these pathways.</p> Methods <p>A four-wave longitudinal design was utilized to examine a moderated sequential mediation model. Participants included 702 college students (<i>M</i>_age = 20.38, <i>SD</i>_age = 1.56) from five universities in China, selected via stratified random sampling. Key variables were assessed at distinct time points to establish temporal precedence. The data were analyzed at the individual level using structural equation modeling to test the hypothesized paths.</p> Results <p>The findings revealed that perceived teacher expectations (T1) positively predicted academic engagement (T4). This relationship was mediated independently and sequentially by basic psychological need satisfaction (T2) and teacher credibility (T3). Furthermore, academic stress moderated the path from perceived teacher expectations to basic psychological need satisfaction, as well as the overall indirect effect on engagement. Specifically, the positive indirect effect was most robust under low levels of academic stress, weaker at average stress, and became non-significant under high stress.</p> Conclusion <p>These findings support the applicability of expectation effects within higher education, elucidating the socio-psychological mechanisms, namely need satisfaction and credibility enhancement, through which teacher expectations foster sustained engagement. Practically, while cultivating high-expectation environments is vital, the motivational benefits are contingent upon students’ levels of academic stress. Therefore, interventions aimed at assisting students in managing academic stress are crucial for maximizing the engagement benefits of positive teacher expectations.</p>