Background and objectives. Major negative life-events including bereavement can precipitate perceived positive life-changes, termed posttraumatic growth (PTG). While traditionally considered an adaptive phenomenon, it has been suggested that PTG represents a maladaptive coping response similar to cognitive avoidance. To clarify the function of PTG, it is crucial to establish concurrent and longitudinal associations of PTG with post-event mental health problems. Yet, longitudinal studies on this topic are scarce. The present study fills this gap in knowledge. Design. A two-wave longitudinal survey was conducted. Methods. Four-hundred and twelve bereaved adults (87.6% women) filled out scales assessing PTG and symptoms of depression, anxiety, prolonged grief, and posttraumatic stress at baseline and 6 months later. Results. The baseline concurrent relationships between all symptom levels and PTG were curvilinear (inverted U-shape). Cross-lagged analyses demonstrated that symptom levels did not predict levels of PTG 6 months later, or vice versa. Conclusions. Findings suggest PTG after loss has no substantive negative or positive effects on mental health. Development of specific treatments to increase PTG after bereavement therefore appears premature.