To provide a presentation assistance system capable of dynamically changing presentation materials according to terms used in a presentation. A presentation assistance system comprises: a presentation material storage unit 3; a related word storage unit 5 which stores a plurality of related words related to the presentation material; a succeeding information storage unit 7 which stores, for each of the related words, information about a succeeding related word that is one or a plurality of related words that are preferably used next; a related word analysis unit 9 which analyzes which one of the related words corresponds to the word analyzed by a term analysis unit; and a succeeding related word selecting unit 11 which selects a succeeding related word from the succeeding information storage unit, by using information about an analyzed related word which is a related word analyzed by the related word analysis unit.