OBJECTIVES: This study aimed to estimate the prevalence of atrial fibrillation (AF) in adults with heart failure (HF) and summarise the all-cause mortality ratio among adult patients with coexisting HF and AF in sub-Saharan Africa (SSA). SETTING: This was a systematic review and meta-analysis of cross-sectional and cohort studies with primary data on the prevalence and incidence of AF among patients with HF and the all-cause mortality ratio among patients with HF and AF in SSA. We combined text words and MeSH terms to search MEDLINE, PubMed and Global Health Library through Ovid SP, African Journals Online and African Index Medicus from database inception to 10 November 2021. Random-effects meta-analysis was used to estimate pooled prevalence. PRIMARY OUTCOME MEASURES: The prevalence and incidence of AF among patients with HF, and the all-cause mortality ratio among patients with HF and AF. RESULTS: Twenty-seven of the 1902 records retrieved from database searches were included in the review, totalling 9987 patients with HF. The pooled prevalence of AF among patients with HF was 15.6% (95% CI 12.0% to 19.6%). At six months, the all-cause mortality was 18.4% (95% CI 13.1% to 23.6%) in a multinational registry and 67.7% (95% CI 51.1% to 74.3%) in one study in Tanzania. The one-year mortality was 48.6% (95% CI 32.5% to 64.7%) in a study in the Democratic Republic of Congo. We did not find any study reporting the incidence of AF in HF. CONCLUSION: AF is common among patients with HF in SSA, and patients with AF and HF have poor survival. There is an urgent need for large-scale population-based prospective data to reliably estimate the prevalence, incidence and risk of mortality of AF among HF patients in SSA to better understand the burden of AF in patients with HF in the region. PROSPERO REGISTRATION NUMBER: CRD42018087564.