The invention provides a smart grid big data information management system based on secure cloud computing and relates to two parts of a smart grid, i.e., cloud computing management and data securitymanagement. The cloud computing management mainly involves area division of the smart grid. Each area is managed by a cloud computing center. The data security management provides secure communicationservice for a cloud computing management frame mainly from such three communication dimensions as top cloud, regional cloud and end-users through combination with a proxy re-encryption scheme of identity-based encryption (IBE) and identity-based signature (IBS), by use of identity rather than digital certificates relying on conventional PKI (Public Key Infrastructure), numerous resources used forcomputing and communication can be saved, and the problem of insecurity of digital certificates in a big data environment is solved.