The variable length coding (VLC) has gained greater attention due to its wide application in the international standard, H.264/AVC and Chinese standard, AVS. A First-one detector is an indispensable module of VLC, such as CAVLC and Exp-Golomb coding. In this paper, a novel First-one implementation architecture is proposed, which can locate the First-one in the codeword in only one cycle. The architecture applies the combinational logic to parse the position of the separator ‘1'. Compared with the conventional methods, this approach has higher efficiency.