Academic Psychological Capital, or PsyCap, – a set of positive psychological resources encompassing hope, efficacy, resilience, and optimism – has begun to gain attention in academia, showing positive relationships with desirable academic outcomes. In the present study, we examine whether academic PsyCap mediates between teacher-student relationships and academic performance as assessed by student’s GPA, using a three-wave longitudinal design. As expected, a statistically significant indirect effect was found between teacher-student relationships and academic performance via academic PsyCap; the better that relationship, the better the performance (download full paper).