Html webpage watermarking technology is a information hiding technology branch, at present several methods have been proposed, but compared to other watermark technology, there still exist problems about watermark embedding difficulties, limited capacity and weak robustness. Aiming at the limited embedding capacity question by using the single label or a symbol in webpage to indicate that a single watermark bit, a method is proposed to use the id value of label in webpage to represent watermark, and the id value of label in webpage can be used to express many watermarking bits. First in this method is to xor with the message digest of the important content in webpage and bits of binary image to represent copyright, and then by the Shamir threshold decomposition scheme, the watermark as the id value of label in webpage is deposited the webpage. Proved by experiments, the scheme has better capacity of embedding, robustness and invisibility.