This study compares a longitudinal population-based sample of spouses bereaved by suicide and those bereaved by other sudden deaths to determine if suicide-bereaved spouses (SBS) experience greater rates of physician-diagnosed mental disorders. Methods: First, married individuals whose spouse died by suicide, sudden natural death (SND) and unintentional injury (UI) were compared to non-bereaved matched cohorts to determine if there were differences in mental disorder rates between bereavement groups and non-bereaved matches. Second, SBS (n=365), spouses bereaved by SND (n=1000), and spouses bereaved by UI (n=270), were compared using inverse probability treatment weighting and generalized estimating equations to calculate relative rates of mental disorders 5 years before/after death. Outcomes: All bereaved cohorts had higher rates of mental disorders compared to non-bereaved cohorts. SBS had the greatest rate of depression post-bereavement (50·96%), followed by UI (38·52%) and SND (33·70%) spouses. When comparing bereavement cohorts, a significant group-by-time interaction (P=0·047) revealed the rate change for depression was significantly different between suicide and UI-bereaved spouses, with SBS having higher rates of depression before bereavement. SBS had increased rates of any mental disorder both pre (ARR=1·35, 95% CI=1·03-1·18, P<·05) and post spousal death (ARR=1·24, 95% CI=1·03-1·45, P<·05) when compared to UI spouses signifying pre-existing mental disorders. Post-bereavement, SBS had greater rates of depression only when compared to SND-bereaved spouses (ARR=1·31, 95% CI=1·10-1·55, P<·01). Interpretation: SBS have the greatest rates of depression and any mental disorder before the death of their spouse, suggesting suicide bereavement may be unique. Sudden spousal bereavement is a vulnerable time for mental disorders.