Minichromosome maintenance 8 (MCM8) is a recently identified member of the minichromosome maintenance family, which possesses helicase and ATPase activity. It interacts with MCM9 and participates in homologous recombination repair. The structure of MCM8 is unclear now. Here, we report the crystal structure of the winged-helix domain of human MCM8 (MCM8-WHD) at 1.21 angstrom resolution. MCM8-WHD adopts a conserved winged-helix architecture. Structure analysis and biochemical study results showed the DNA binding ability and crucial residues of MCM8-WHD. Our results are helpful to understand the function of MCM8. (C) 2020 Elsevier Inc. All rights reserved.