Abstract: In the traditional CBR rate control algorithm, the skipping method is adopted to combat the overflow of video buffer , in which the motion compensation error and picture distortion are increased with the number of skipping frame. To deal with the disadvantage of traditional skipping method, a new adaptive rate control algorithm with spatial scalability for video coding is presented in this paper. In the method, the original skipped frame is adaptively sub-sampled at encoder and is up-sampled in decoder. Simulation results show that this scheme can highly improve the quality of reconstructed video and obtain a gain of about0.3~0.8dB and 0.1~0.4dB in PSNR respectively compared with the traditional skipping method and the method of increasing quantization step.