This study examines the relationship between university graduates' proactive personality and two early employment outcomes (i.e., employment status and perceived overqualification). Specifically, we propose two moderated mediation models, one for each employment outcome, with career planning as a mediator and core self-evaluations as a moderator in the proactive personality-employment outcomes link. The study sample consisted of 315 graduates, and a time-lagged design with two data-collection points was implemented. When the outcome was employment status, contrary to our expectations, the indirect effect of proactive personality via career planning was not moderated by core self-evaluations. However, when the outcome was perceived overqualification, the results showed that core self-evaluations moderated the negative indirect effect of proactive personality on perceived overqualification via career planning. Specifically, the relationship was stronger when core self-evaluations were low than when they were high, reinforcing concerns in the literature about the costs of high core self-evaluations. We discuss implications for theory and research on proactive career self-management.