A method and an apparatus for waking up a wireless device to resolve a problem that power consumption and communication overheads are large during wake-up of a wireless device. The method includes obtaining, by a first wireless device, indication information of at least one second wireless device using a main communications circuit of the first wireless device, where the indication information includes at least one of a power saving requirement or wake-up capability information, determining, by the first wireless device, an operation mode of an auxiliary wake-up circuit of the first wireless device based on a quantity of second wireless devices or the indication information, and receiving, by the auxiliary wake-up circuit of the first wireless device based on the operation mode, a wake-up packet from the second wireless device to wake up the main communications circuit of the first wireless device.