Abstract: Information hiding can hide secret messages inside of image, video, audio, text, and other digital objects. To a casual observer inspecting these, the messages are invisible. Information hiding has become a new research hotspot of information security and copyright protection of digital multimedia content recently. Webpage information hiding algorithm uses a webpage as cover-object. Based on equal tag, an algorithm of webpage information hiding is presented in this paper, which overcomes the shortcoming of the ability of imperceptibility and the ability of contradict with the machine filtration of traditional webpage information hiding algorithms, and improves the embedded capacity of the algorithm based on the order of attributes pair. According to the embedded rule, firstly a secret message M is changed to a large integer N, and then the large integer N is embedded into the cover webpage by changing the tag to its equal tag. The experimental results and analysis show that the algorithm does not length the size of cover-webpage, and has good imperceptibility and perfect security than the traditional algorithm. The embedded capacity of the algorithm gets better increase than the algorithm based on the order of attributes pair. So the algorithm could be used to protect the content of a webpage and covert communication.