This paper presents a novel frame-skipping transcoding scheme for improving picture quality and reducing computational complexity. Performing in the discrete cosine transform (DCT) domain, it eliminates the high computation from the process of DCT and inverse DCT (IDCT). To maintain an acceptable video quality after frame-rate conversion, the proposed scheme uses two strategies: one is transferring macroblock (MB) coding code by a judgment criterion to reduce the drift error, and the other is re-calculating the prediction residual to minimize the re-encoding error. Furthermore, the transcoder use a structure comprised of a separate decoder and a partial encoder to enhance the implementation efficiency. Simulation results show that, as compared to traditional transcoders, the proposed transcoder has a lower complexity and higher performance.