A method for providing information about a main knowledge stream is disclosed. According to an embodiment of the present invention, the method includes obtaining reference links representing reference relationships among reference documents in each of a plurality of documents stored in a database, determining one or more basic paths connecting the reference links, calculating probability values of the reference links by overlapping the determined basic paths, determining a first document among the documents and an input reference link associated with the first document, and performing a Markov chain model using a probability value of the input reference link, and calculating information about the main knowledge stream associated with the first document using the result obtained by performing the Markov chain model.