An adaptive channel bandwidth switching method, comprising: buffering, by a sending end device, service data to be sent; sending, by the sending end device, a first microwave frame to a receiving end device according to a symbol rate corresponding to an initial channel bandwidth, wherein a frame header of the first microwave frame indicates that a next frame is a transition frame, and that a symbol rate of the next frame is a symbol rate corresponding to a target channel bandwidth, and a payload portion of the first microwave frame carries a random symbol; performing, by the receiving end device, a receiving configuration for the transition frame with a symbol rate of the symbol rate corresponding to the target channel bandwidth after processing the first microwave frame; continuously sending, by the sending end device, second microwave frames to the receiving end device according to the symbol rate corresponding to the target channel bandwidth, wherein a frame header of the second microwave frame indicates that a next frame is a transition frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the second microwave frame carries a random symbol; switching, by the receiving end device, a configuration related to the symbol rate after receiving the second microwave frames; performing, by the receiving end device, symbol synchronization; performing, by the receiving end device, frame synchronization; performing, by the receiving end device, equalizer convergence; sending, by the sending end device, a third microwave frame to the receiving end device according to the symbol rate corresponding to the target channel bandwidth after the receiving end device performs the equalizer convergence, wherein a frame header of the third microwave frame indicates that a next frame is a normal frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the third microwave frame carries a random symbol; performing, by the receiving end device, a receiving configuration for the normal frame with a symbol rate of the symbol rate corresponding to the target channel bandwidth after processing the third microwave frame; stopping buffering, by the sending end device, the service data to be sent; and sending, by the sending end device, a fourth microwave frame to the receiving end device according to the symbol rate corresponding to the target channel bandwidth, wherein a frame header of the fourth microwave frame indicates that a next frame is a normal frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the fourth microwave frame carries a service symbol, so as to switch the channel bandwidth. buffering, by a sending end device, service data to be sent; sending, by the sending end device, a first microwave frame to a receiving end device according to a symbol rate corresponding to an initial channel bandwidth, wherein a frame header of the first microwave frame indicates that a next frame is a transition frame, and that a symbol rate of the next frame is a symbol rate corresponding to a target channel bandwidth, and a payload portion of the first microwave frame carries a random symbol; performing, by the receiving end device, a receiving configuration for the transition frame with a symbol rate of the symbol rate corresponding to the target channel bandwidth after processing the first microwave frame; continuously sending, by the sending end device, second microwave frames to the receiving end device according to the symbol rate corresponding to the target channel bandwidth, wherein a frame header of the second microwave frame indicates that a next frame is a transition frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the second microwave frame carries a random symbol; switching, by the receiving end device, a configuration related to the symbol rate after receiving the second microwave frames; performing, by the receiving end device, symbol synchronization; performing, by the receiving end device, frame synchronization; performing, by the receiving end device, equalizer convergence; sending, by the sending end device, a third microwave frame to the receiving end device according to the symbol rate corresponding to the target channel bandwidth after the receiving end device performs the equalizer convergence, wherein a frame header of the third microwave frame indicates that a next frame is a normal frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the third microwave frame carries a random symbol; performing, by the receiving end device, a receiving configuration for the normal frame with a symbol rate of the symbol rate corresponding to the target channel bandwidth after processing the third microwave frame; stopping buffering, by the sending end device, the service data to be sent; and sending, by the sending end device, a fourth microwave frame to the receiving end device according to the symbol rate corresponding to the target channel bandwidth, wherein a frame header of the fourth microwave frame indicates that a next frame is a normal frame, and that a symbol rate of the next frame is the symbol rate corresponding to the target channel bandwidth, and a payload portion of the fourth microwave frame carries a service symbol, so as to switch the channel bandwidth.