A System-on-Chip Design of VLD (Variable Length Decoder) in multi-standard video decoder is proposed in this paper. Our design supports all the popular video compression standards, e.g. MPEG-1, MPEG-2, MPEG-4, H.264, AVS, RealVideo. Benefit from its low power, the design is especially suitable for wearable multimedia applications. Simulation results show that the whole design takes an area of 1.04mm2, under a 0.13um CMOS technology. In the frequency as low as only 133MHz, it can meet the demands of HD (High Definition) requirements.