PURPOSE: The early loss of a parent is a tragedy and a serious life event. This study investigated grief resolution and morbidity in cancer-bereaved teenagers 6 to 9 years after the loss of a parent to cancer. METHODS: In a nationwide population-based study of 622 of 851 (73 %) youths who as teenagers 6 to 9 years earlier had lost a parent to cancer, we explored the magnitude of unresolved grief and its association with psychological and physiological morbidity. Participants answered a study-specific anonymous questionnaire including questions about if they had worked through their grief and about their current health. RESULTS: Six to nine years post-loss 49 % reported unresolved grief (8 % no and 41 % a little grief resolution). They had, in comparison with youths reporting resolved grief, statistically significantly elevated risks, e.g. for insomnia (sons' relative risk (RR) 2.3, 95 % CI 1.3-4.0; daughters' RR 1.7, 95 % CI 1.1-2.7), fatigue (sons' RR 1.8, 95 % CI 1.3-2.5; daughters' RR 1.4, 95 % CI 1.1-1.7) and moderate to severe depression, i.e. score >9, PHQ-9 (sons' RR 3.6, 95 % CI 1.4-8.8; daughters' RR 1.8, 95 % CI 1.1-3.1). Associations remained for insomnia in sons, exhaustion in daughters and fatigue in both sons and daughters when depression, negative intrusive thoughts and avoiding reminders of the parents' disease or death were included in a model. CONCLUSIONS: Approximately half of cancer-bereaved youth report no or little grief resolution 6 to 9 years post-loss, which is associated with fatigue, sleeping problems and depressive symptoms.