This paper presents a resolution enhancement algorithm in an asymmetric resolution stereo video for improving the video resolution. In this stereo video architecture, a scene is captured by two cameras to form two views, one view is a lower-resolution video and the other is a full-resolution video. The goal is to enhance the lower-resolution video to a full-resolution video. In the lower-resolution video, frames synchronized with full-resolution video are enhanced via disparity estimation algorithm, while the rest frames are improved by mono-view video super-resolution based on key frames method. The experimental results demonstrate that the proposed method is effective for both visual and objective qualities.