The invention discloses an ordering method and an ordering device for an information retrieval system. The method comprises: receiving query information; retrieving according to the query information, to obtain a document collection in initial ordering, the document collection in initial ordering being a document collection after retrieved result documents are sorted according to correlation values of the retrieved result documents and the query information; in an ordering rule base, obtaining an ordering rule collection related to the query information and the document collection in initial ordering; and according to the document collection in initial ordering and the ordering rule collection, performing post ordering, to generate a final ordering document collection. Through the above method, the method can satisfy complicated and various retrieval demands in dynamic changes, and can automatically manage and maintain the rule base.