College students face much instability and challenge across multiple spheres of functioning. The transition from late youth into early adulthood with new social, scholastic, and living environments presents heightened risks for destabilising academic motivation and mental health. Using the taxonomy of multidimensional academic amotivation, this study examines the reciprocal within-person relationships between academic amotivation and depressive symptoms over time among early-staged college students. 488 first- and second-year undergraduates reported their amotivation and depressive symptoms at three intervals within a semester. Random-intercepts cross-lagged panel models were applied to evaluate the temporal priority in the interrelations. Results revealed that the paths from depressive symptoms to amotivation were consistent and stable, but the cross-lags from amotivation to depressive symptoms were varied with dimensional characteristics. While the paths from amotivation due to low ability and low effort to depressive symptoms demonstrated strong reciprocal relationships, the ones due to low value and unappealing tasks did not. Findings confirm that there is a complex and dynamic web of interrelationships between amotivation and depressive symptoms. College students' motivational deficits in learning may not only be causes but also consequences of mental health.