Using the Semantic Web & Data Mining Schemes to Filter Pornography Webpages Abstract Today's Internet is filled with a variety of pornographic information. Protecting the adolescents and children from the influence of illegal information and pornography is a crucial issue.At present, most filtering systems focus on percolating pornographic and violent information. However, a variety of legal and normal websites are also filtered out by these systems even though the websites contain sex and violence related information.Therefore, this study utilized the Semantic Web and data mining techniques to distinguish between legal and sex-violence websites and improved the accuracy of information filtering. The system adopted Data mining technology TF / IDF for weight analysis. The browse files termed by the CKIP-off, and then calculated each word in the document off the weight value. Finally, the system selected the line weight default value of breaking the word and the ontology knowledge base for comparison.Through the ontological structure of the system, this study checked the file association between the breaking words. Then, this study further inferred the implicit rules by Jena in order to justify the browsing files of websites. Finally, this system, based on the justification results, presented the illustrations to inform the problems in user’s browsing information. Keyword: Semantic Web、Ontology、CKIP、TF/IDF Weight Analysis。