With reference to Table 2, it can be learned that, in the configuration of plurality of wake up signals, the category information classified based on service feature information includes two categories, namely, the uplink service trigger and the downlink service trigger. The uplink service trigger corresponds to the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4. The downlink service trigger corresponds to the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8. When the to-be-monitored wake up signal is determined in the plurality of wake up signals based on the first category and the grouping factor, with reference to the foregoing method 1, if a first type to which the terminal device belongs is the category of the uplink service trigger, to-be-determined wake up signals may be first determined in the eight wake up signals based on the category of the uplink service trigger, where the to-be-determined wake up signals are the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4; and then, the to-be-monitored wake up signal that the terminal device needs to monitor is further determined in the four to-be-determined wake up signals: the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4, based on a remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device. Specifically, if the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 0, it is determined, in the four to-be-determined wake up signals: the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4 and based on the group 1, that the to-be-monitored wake up signal is the wake up signal 1. In other words, the terminal device needs to monitor only the wake up signal 1, and does not need to monitor the other seven wake up signals. If the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 1, it is determined, in the four to-be-determined wake up signals: the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4 and based on the group 2, that the to-be-monitored wake up signal is the wake up signal 2. In other words, the terminal device needs to monitor only the wake up signal 2, and does not need to monitor the other seven wake up signals. If the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 2, it is determined, in the four to-be-determined wake up signals: the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4 and based on the group 3, that the to-be-monitored wake up signal is the wake up signal 3. In other words, the terminal device needs to monitor only the wake up signal 3, and does not need to monitor the other seven wake up signals. Specifically, if the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 3, it is determined, in the four to-be-determined wake up signals: the wake up signal 1, the wake up signal 2, the wake up signal 3, and the wake up signal 4 and based on the group 4, that the to-be-monitored wake up signal is the wake up signal 4. In other words, the terminal device needs to monitor only the wake up signal 4, and does not need to monitor the other seven wake up signals. In this way, the to-be-monitored wake up signal is determined in the plurality of wake up signals based on the foregoing method 1. On the contrary, if a first type to which the terminal device belongs is the category of the downlink service trigger, to-be-determined wake up signals may be first determined in the eight wake up signals based on the category of the downlink service trigger, where the to-be-determined wake up signals are the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8; and then, the to-be-monitored wake up signal that the terminal device needs to monitor is further determined in the four to-be-determined wake up signals: the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8, based on a remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device. Specifically, if the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 0, it is determined, in the four to-be-determined wake up signals: the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8 and based on the group 1, that the to-be-monitored wake up signal is the wake up signal 5. In other words, the terminal device needs to monitor only the wake up signal 5, and does not need to monitor the other seven wake up signals. If the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 1, it is determined, in the four to-be-determined wake up signals: the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8 and based on the group 2, that the to-be-monitored wake up signal is the wake up signal 6. In other words, the terminal device needs to monitor only the wake up signal 6, and does not need to monitor the other seven wake up signals. If the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 2, it is determined, in the four to-be-determined wake up signals: the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8 and based on the group 3, that the to-be-monitored wake up signal is the wake up signal 7. In other words, the terminal device needs to monitor only the wake up signal 7, and does not need to monitor the other seven wake up signals. Specifically, if the remainder obtained after the modulo-4 operation is performed on the identifier of the terminal device is 3, it is determined, in the four to-be-determined wake up signals: the wake up signal 5, the wake up signal 6, the wake up signal 7, and the wake up signal 8 and based on the group 4, that the to-be-monitored wake up signal is the wake up signal 8. In other words, the terminal device needs to monitor only the wake up signal 8, and does not need to monitor the other seven wake up signals. In this way, the to-be-monitored wake up signal is determined in the plurality of wake up signals based on the foregoing method 1.