There is provided an information processing apparatus for presenting knowledge information that is similar to inputted knowledge information, by using a knowledge system including relation information between a plurality of knowledge information items, the apparatus comprising: an input unit configured to receive first knowledge information, and second knowledge information that is associated with the first knowledge information; a relation acquisition unit configured to acquire first relation information indicating a relation that the first knowledge information has with respect to the second knowledge information, from the knowledge system; a knowledge acquisition unit configured to acquire knowledge information that has the relation indicated by the first relation information with respect to the second knowledge information, from the knowledge system; and an output unit configured to output the knowledge information acquired by the knowledge acquisition unit as knowledge information similar to the first knowledge information.