1. A method for creating a speech recognition dictionary that is used for creating first document data through voice input in an application, the method comprising the steps of: detecting if a document data creation processing is started; reading second document data obtained by the application when the document data creation processing is started; analyzing the second document data read and extracting at least one unknown word therefrom that does not exist in an existing speech recognition dictionary; and creating a speech recognition dictionary containing the at least one unknown word.