The invention discloses a method and system for playing back game video. The method comprises the steps that corresponding executing instructions are executed by responding to the game battle operation of a game system, and basic game information, the successfully-executed executing instructions and corresponding role IDs generate video files to be uploaded to a server; a playback request is sent to the server by responding to a video playback request instruction input by a user; the video files returned by the server are obtained, the corresponding basic game information, all the executing instructions and the corresponding role IDs are obtained after the video files are analyzed, and then the video is played. The video is played back according to instruction data by storing the relevant instruction data of the video, the size is small, few resources are consumed, the process is simple, and implementation is convenient. The video of a game battle can be played back truly and accurately, and can be shared and spread conveniently, and the method and system can be widely applied to video playback in the field of games.