A method for mode switching for a Wireless Local Area Network, WLAN, wherein the WLAN is according to an IEEE 802.11 technology, and the method comprises: indicating, by an Access Point, AP, its own current working mode to a non-AP associated with the AP by a system configuration message; instructing, by the AP, the non-AP associated with the AP to switch a working mode by a first frame exchange sequence; and switching, by the non-AP, the working mode according to instruction information included in the first frame exchange sequence after the non-AP receives the first frame exchange sequence; wherein the working mode refers to that a data transmission signal is transmitted by a channel defined by a channelized set and a corresponding bandwidth, or a frame exchange sequence is transmitted by a channel defined by one or more channelized sets and a corresponding bandwidth; wherein the channelized set refers to a set consisting of multiple channels of 20 MHz defined from a predefined or fixed start frequency and multiple broadband channels consisting of the multiple channels of 20 MHz in a given frequency band; and the frame exchange sequence refers to the sending of a series of wireless frames and corresponding wireless frame feedback required to complete one data transmission; and wherein the process of instructing by the AP the non-AP associated with the AP to switch the working mode comprises: instructing, by the AP in a working mode 1, the non-AP associated with the AP by the first frame exchange sequence that data will be sent in a working mode 2 subsequently and notifying by the first frame exchange sequence a first maximum duration for sending data in the working mode 2 to the non-AP associated with the AP; switching the AP and the non-AP to the working mode 2 to transmit data within a first specified time according to instruction after triggering of the first frame exchange sequence for mode switching is completed; and switching the AP and the non-AP back to the working mode 1 at once after data transmission is completed in the working mode 2; wherein the working mode 1 is a first or second working mode, and correspondingly, the working mode 2 is a second or first working mode. indicating, by an Access Point, AP, its own current working mode to a non-AP associated with the AP by a system configuration message; instructing, by the AP, the non-AP associated with the AP to switch a working mode by a first frame exchange sequence; and switching, by the non-AP, the working mode according to instruction information included in the first frame exchange sequence after the non-AP receives the first frame exchange sequence; wherein the working mode refers to that a data transmission signal is transmitted by a channel defined by a channelized set and a corresponding bandwidth, or a frame exchange sequence is transmitted by a channel defined by one or more channelized sets and a corresponding bandwidth; wherein the channelized set refers to a set consisting of multiple channels of 20 MHz defined from a predefined or fixed start frequency and multiple broadband channels consisting of the multiple channels of 20 MHz in a given frequency band; and the frame exchange sequence refers to the sending of a series of wireless frames and corresponding wireless frame feedback required to complete one data transmission; and wherein the process of instructing by the AP the non-AP associated with the AP to switch the working mode comprises: instructing, by the AP in a working mode 1, the non-AP associated with the AP by the first frame exchange sequence that data will be sent in a working mode 2 subsequently and notifying by the first frame exchange sequence a first maximum duration for sending data in the working mode 2 to the non-AP associated with the AP; switching the AP and the non-AP to the working mode 2 to transmit data within a first specified time according to instruction after triggering of the first frame exchange sequence for mode switching is completed; and switching the AP and the non-AP back to the working mode 1 at once after data transmission is completed in the working mode 2; wherein the working mode 1 is a first or second working mode, and correspondingly, the working mode 2 is a second or first working mode. instructing, by the AP in a working mode 1, the non-AP associated with the AP by the first frame exchange sequence that data will be sent in a working mode 2 subsequently and notifying by the first frame exchange sequence a first maximum duration for sending data in the working mode 2 to the non-AP associated with the AP; switching the AP and the non-AP to the working mode 2 to transmit data within a first specified time according to instruction after triggering of the first frame exchange sequence for mode switching is completed; and switching the AP and the non-AP back to the working mode 1 at once after data transmission is completed in the working mode 2; wherein the working mode 1 is a first or second working mode, and correspondingly, the working mode 2 is a second or first working mode.