Objective: Two small studies have suggested that family carers of people with dementia may be a high-risk group for suicide. The objective of this study was to further explore the rate of suicidal ideation in a large sample of carers and identify psychosocial risk and protective factors.Method: A cross-sectional survey was conducted with 566 family carers. The survey included measures of suicidality, self-efficacy, physical health, depression, anxiety, hopelessness, optimism, burden, coping strategies, and social support.Results: Sixteen percent of carers had contemplated suicide more than once in the previous year. There were univariate differences between suicidal and non-suicidal carers on self-efficacy, social support, coping, burden, depression, anxiety, hopelessness, optimism, reasons for living, and symptoms of dementia, as well as age and income management. In a multivariate model, age, depression, and reasons for living predicted suicidal ideation. In tests for mediation, satisfaction with social support and dysfunctional coping had indirect effects on suicidal ideation via depression.Conclusion: Family carers of people with dementia have high rates of suicidal ideation, with depression a risk factor and increasing age and reasons for living as protective factors. Depression and reasons for living should be targeted in interventions to reduce suicide risk in dementia carers.