The eukaryotic GINS complex is essential for the establishment of DNA replication forks and replisome progression. We report the crystal structure of the human GINS complex. The heterotetrameric complex adopts a pseudo symmetrical layered structure comprising two heterodimers, creating four subunit-subunit interfaces. The structural and biochemical data suggest that the tetrameric complex ensures a stable platform for the C-terminal domain of Psfl to act as a key interaction interface for other proteins in the replication-initiation process.