BACKGROUND: Cash transfers, payments provided by formal or informal institutions to recipients, are increasingly used in emergencies. While increasing autonomy and being supportive of local economies, cash transfers are a cost-effective method in some settings to cover basic needs and extend benefits of limited humanitarian aid budgets. Yet, the extent to which cash transfers impact health in humanitarian settings remains largely unexplored. This systematic review evaluates the evidence on the effect of cash transfers on health outcomes and health service utilisation in humanitarian contexts. METHODS: Studies eligible for inclusion were peer reviewed (quantitative,qualitative and mixed-methods). Nine databases (PubMed, EMBAS, Medline, CINAHL, Global Health, Scopus, Web of Science Core Collection, SciELO and LiLACS) were searched without language and without a lower bound time restriction through 24 February 2021. The search was updated to include articles published through 8 December 2021. Data were extracted using a piloted extraction tool and quality was assessed using The Joanna Briggs Critical Appraisal Tool. Due to heterogeneity in study designs and outcomes, results were synthesised narratively and no meta-analysis was performed. RESULTS: 30 673 records were identified. After removing duplicates, 17 715 were double screened by abstract and title, and 201 in full text. Twenty-three articles from 16 countries were included reporting on nutrition outcomes, psychosocial and mental health, general/subjective health and well-being, acute illness (eg, diarrhoea, respiratory infection), diabetes control (eg, blood glucose self-monitoring, haemoglobin A1C levels) and gender-based violence. Nineteen studies reported some positive impacts on various health outcomes and use of health services, 11 reported no statistically significant impact on outcomes assessed and 4 reported potential negative impacts on health outcomes. DISCUSSION: Although there is evidence to suggest a positive relationship between cash transfers and health outcomes in humanitarian settings, high-quality empirical evidence, that is methodologically robust, investigates a range of humanitarian settings and is conducted over longer time periods is needed. This should consider factors influencing programme implementation and the differential impact of cash transfers designed to improve health versus multipurpose cash transfers. PROSPERO REGISTRATION NUMBER: CRD42021237275.