The invention relates to a power system energy efficiency public service cloud platform based on cloud computing. A three-layer framework is adopted in the energy efficiency public service cloud platform and comprises an energy efficiency service Iaas layer, an energy efficiency service Paas layer and an energy efficiency service application Saas layer. The energy efficiency service Iaas layer is an infrastructure level service layer and is used for providing virtual resources, mapped through the virtual technology, for a network, a server and database physical facilities in the cloud platform. The energy efficiency service Paas layer is a platform level service layer and used for providing the execution environment of cloud middleware resources, a distributed parallel platform and application service software for power consumers. The energy efficiency service application Saas layer is a software level service layer and used for providing software services of energy efficiency services based on Web access for users. According to the energy efficiency public service cloud platform, acquisition and monitoring of energy efficiency information and diagnosis and analysis of user energy efficiency parameters are achieved through the energy efficiency service application Saas layer. By means of the framework mode, management objects and function requirements can be quickly expanded and upgraded, and user energy management efficiency is improved.