ABSTRACT Objectives: Grief research in family carers of people with dementia has increased. We aimed to report the prevalence of pre-death and post-death grief and to synthesize associated factors and the relationship between pre-death factors and post-death grief and services used to manage grief. Design: (Prospero protocol: CRD42020165071) We systematically reviewed literature from PsycINFO, MEDLINE, CINAHL, and ASSIA until April 2020. Effectiveness of intervention data and studies not written in English were excluded; qualitative studies were additionally excluded during study selection. Study quality was assessed using the Mixed Methods Appraisal Tool. Evidence was narratively summarized. Participants: Family non-paid carers of somebody with any dementia type. Measurements: Validated measures of pre-death and/or post-death grief. Results: We included quantitative data from 55 studies (44 rated as high quality). Most included solely spouse or adult child carers. Forty-one studies reported pre-death grief, 12 post-death grief, and 6 service use; eight were longitudinal. 17% met the Prolonged Grief Disorder criteria pre-death (n = 1) and 6–26% (n = 4) of participants met the Complicated Grief criteria post-death. Being a spouse, less educated, caring for somebody with advanced dementia, and greater burden and depression were associated with higher pre-death grief. Lower education level and depression were predictive of higher post-death grief. Pre-death factors found to influence post-death grief were grief and depression. Limited service use evidence was reported. Conclusion: Awareness of characteristics which increase the likelihood of higher grief can help identify those in need of support. Future research should focus on what supports or services are beneficial to grief experiences.