Iron is essential for both humans and pathogens, yet its genetic regulation remains understudied in African populations. Here, we report genome-wide association studies of six iron-related biomarkers in 3928 children from five sites across Africa, with replication in 2868 African American adults and investigate associations with severe malaria and bacteremia. We identify previously unreported loci at genome-wide significance, for transferrin at GTF3C5, and for hepcidin at CHCHD7/SDR16C5. Variants tagging the DUP4 haplotype, encoding the Dantu blood group (rs552439837) are associated with soluble transferrin receptor levels. Variants at GTF3C5 (rs2905094) and DUP4 confer protection against severe malaria and bacteremia. The CHCHD7/SDR16C5 variant (rs73596248) increases hepcidin levels and is associated with reduced risk of Klebsiella pneumoniae and Staphylococcus aureus bacteremia. Polygenic risk scores derived from European data show limited transferability to African populations. In this work, we demonstrate new genetic insights into iron regulation and highlight iron's role in host-pathogen interactions.