A method, an apparatus, and a system for quality of service (QoS) parameter configuration in a wireless local area network (WLAN), where the method includes sending, by a network device, a default first QoS parameter set to a terminal, sending, by the network device, a QoS parameter set modification message including a second QoS parameter set to the terminal, where the second QoS parameter set is different from the first QoS parameter set, and the QoS parameter set modification message is a unicast beacon frame or an active probe response frame. In this way, the second QoS parameter set different from the first QoS parameter set is sent to the terminal using the unicast beacon frame or the active probe response frame, which ensures that the network device dynamically adjusts a QoS parameter set of the terminal on a per terminal basis, thereby improving data transmission efficiency and user experience.