The invention discloses a method and device for embedding a watermark of a stereo video and a method for extracting the watermark of the stereo video. The method for embedding the watermark of the stereo video includes embedding a watermark identification sequence in a stereo video frame; obtaining a global parallax error between a left image and a right image of the stereo video frame, and obtaining a left matching image and a right matching image according to the global parallax error; obtaining a correlation coefficient between the left matching image and the right matching image, and generating an embedding mode coefficient according to a comparison relation between a correlation coefficient and watermark information; and a storage key which includes an embedded mode coefficient, the global parallax error and watermark information capacity. According to the method for embedding the watermark of the stereo video, through a zero-watermark technology which comprehensively utilizes a global parallax error characteristic of the stereo video, after the watermark information is embedded in the stereo video, video data is not damaged, the problem that a stereo video image is modified when a watermark image is embedded is avoided, and thus a video watching effect is not influenced.