The present disclosure can provide a method, device, terminal and system for transmitting data. The method for transmitting data includes: receiving target data from a target gateway via a channel to be detected; detecting whether an interference signal from another terminal for data transmission with the target gateway exists on the channel to be detected within the preset frame interval duration; and stopping receiving the target data when the interference signal exists until the channel to be detected is determined to be idle, and continuing to receive the target data via the idle channel to be detected.