A method for online video playback includes: loading the first video segment corresponding to the lowest class of bit rates from the version of the lowest class of bit rates at an initial playback; and choosing to load and play a video segment corresponding to an appropriate class of bit rates according to the bit rate corresponding to the current network traffic and the resolution supported by a playing terminal after the video has been playing steadily. The method for online video playback can automatically choose to play videos encoded at an appropriate bit rate according to the current internet speed so that the playback is smooth and uninterrupted.