The present invention provides a method, an apparatus, and a network management system for acquiring an energy efficiency parameter of a network with overlaid coverage, and a radio access network device and a communication system. The network management system can acquire, via the radio access network device, the performance measurement parameter of the target cell in the energy efficiency measurement area and the energy consumption value of the radio access network device to which the target cell in the energy efficiency measurement area belongs, then the network management system further acquires the energy efficiency parameter of the energy efficiency measurement area in the network with overlaid coverage, so as to help an operator with accurately learning about the actual gain brought by the cell energy saving use case.