In this paper a low cost and low power multi-mode entropy decoder is proposed. The proposed design is compatible to the entropy decoding for JPEG, MPEG-1/2/4, H.264 and VC-1 video coding standards. It adopts the code-word tables merging and sharing, and integrates the various entropy decoding into a single programmable design. To reduce the required memory space, a generic look-up table partition strategy covering various video coding standards is proposed. Besides, the low power concept of high probability data path with lower capacitance is also taken into account. The proposed multi-mode entropy decoder is implemented using TSMC 0.13μm at the cost of 113,884 gates and 0.54KB SRAM. Its maximum operating frequency achieves 166MHz, which can support entropy decoding on high definition video larger than HD1080@48fps.