We present the storage architecture and the backup strategy of ENEAGRID, the computing infrastructure of ENEA. Data are organized in two file systems: AFS of∼40 TB and IBM GPFS of∼1.3 PB. AFS is geographically distributed and provides a common work environment for accessing services and computing resources independently of the location of users. GPFS is mainly used by parallel applications to better exploit the potentiality of HPC CRESCO clusters, the main computing facilities of ENEAGRID.