Perfectionistic concerns (i.e., negative reactions to failures, exaggerated concerns over others’ criticism and expectations, and nagging self-doubts) are linked to social disconnection and depressive symptoms. According to the perfectionism social disconnection model, perfectionistic concerns contribute to social disconnection (i.e., feeling rejected, excluded, and unwanted by others) which, subsequently, contributes to depressive symptoms. The social world is replete with chances for interpretations. In interpreting their social worlds, people high in perfectionistic concerns tend to perceive interpersonal discrepancies, a distressing form of social disconnection that involves perceptions of others as dissatisfied with them and as disapproving of them. These interpretations are also conceptualized as having depressing consequences for people high in perfectionistic concerns. This study tested whether perceived interpersonal discrepancies mediate the relation between perfectionistic concerns and depressive symptoms; 240 participants were recruited and this mediational model was tested with a four-wave, 4-week longitudinal design. Structural equation modeling with bootstrapped tests of mediation indicated the perfectionistic concerns- depressive symptoms relationship was mediated by interpersonal discrepancies (even after controlling for perfectionistic strivings). People high in perfectionistic concerns perceive others as dissatisfied with them and as disapproving of them. Feeling rejected, excluded, and unwanted by others, people high in perfectionistic concerns are vulnerable to depression.