The invention relates to a length-adjustable anti-static sock. The length-adjustable anti-static sock is characterized in that the sock comprises a sock body (1), the top of the sock body (1) is provided with a sock leg (2), the bottom of the sock leg (2) is fixed with the top of the sock body (1) through hook-and-loop fasteners (3), the sock body (1) comprises a fabric layer (4), the bottom face of the fabric layer (4) is provided with a fluff layer (5), the bottom face of the fluff layer (5) is provided with an anti-static layer (6), lower-layer air holes are formed in the anti-static layer (6), and upper-layer air holes are formed in the fabric layer (4). According to the length-adjustable anti-static sock, the sock leg is additionally arranged on the top of the sock body and fixed with the sock body through the hook-and-loop fasteners, the sock leg can be disassembled conveniently when the sock leg needs to be disassembled, and therefore the length of the sock can be adjusted; in addition, the rear end of the sock is provided with the anti-static layer, and the sock can be suitable for static isolation.