The present application discloses a data transmission method, including: receiving a screen mirroring request from a screen mirroring terminal device, and establishing an audio and video data connection channel with the screen mirroring terminal device; obtaining audio and video data through the audio and video data connection channel and playing the audio and video data; monitoring a network status of the audio and video data connection channel; and when the network status deteriorates, selecting a transmission mode from preset transmission strategies corresponding to an indicator value of the network status and performing the transmission mode.