The invention relates to a webpage link protection method based on control character coding and steganography. Watermark information can be embedded through selected control characters which are not displayed at a browser end, and thus link information in a webpage can be protected. First, the webpage is partitioned into blocks according to links, watermark information with any bit is generated according to all the characters of all the sub-blocks and coded into corresponding control characters to be embedded into the webpage, and a webpage with watermarks is generated; in detection, whether the link blocks are tampered or not is judged by comparing the relations between different bit numbers and thresholds of extracted watermarks and reconstructed watermarks corresponding to the link blocks; when tampered link blocks are detected, all attribute information including link addresses is deleted, and blocks are marked with warning mark information, so that a prompt is given to a user. Through the webpage link protection method based on control character coding and steganography, link block information in the webpage can be effectively protected; when the link blocks are tampered, the tampering can be detected out in time, and false information is prevented from being propagated, so that negative effects of tampered link blocks on images ad business of enterprise and public institutions are reduced.