The present invention provides a method and a base station for managing capacity of a wireless communication network, which relates to the field of wireless communications and is capable of saving energy while adjusting capacity of a wireless communication network of a base station. The present invention includes: checking total traffic of all overlay networks belonging to the base station; if the checked total traffic keeps being lesser than a preset load threshold, searching for and determining a first overlay network; maintaining normal work of a power amplifier of at least one antenna in each group of antennas in the first overlay network and turning off power amplifiers of one or more other antennas; and connecting the one or more other antennas to the power amplifiers maintaining normal work in the groups in which the one or more other antennas are located.