Abstract: A mass of distributed and dynamic information on the Web has resulted in “information overload”. With the flood of information, it has become an important research issue to search the Web based on traditional information retrieval technology. However, various systems and ambiguous terminology of information retrieval on the Web bring much trouble to users in application and researchers in development as well. Moreover, there are few publications which roundly analyze technologies up to the minute in this field. The state of the art of information retrieval on the Web is surveyed in this paper. First categorized are the systems of sorts in a hierarchical taxonomy and each layer is examined thoroughly. Then analyzed are the general mechanism and several critical new technologies involved in information retrieval on the Web, including results ranking based on hyperlinks, online clustering of retrieval results, concept search, relevance feedback and so on. The paper ends with the authors’ achievement and future work.