With the rapid development of knowledge economy and the fact of China joining the WTO, knowledge property has been playing a more and more important roll in the process of economy evolution. Facing the competition challenge of international market integration and restriction of international market regulation, we have to be highly aware of the importance of knowledge property, enhancing people s consciousness to patent , and promoting the invention, usage and protection to patent. This paper discusses the usefulness of patent documentation in the WTO situation and the retrieval and usage of patent documentation on the internet.