PURPOSE: To reduce trouble in data exchange between different kinds of equipment by performing KANA(Japanese syllabary)-KANJI(Chinese character) conversion on the basis of a morpheme analysis or meaning analysis of an inputted KANA character string, and storing font data which can be specified with a font code and a different type code.

CONSTITUTION: A KANA-KANJI conversion execution part 23 sends out the different type code to a KANA-KANJI conversion control part 22 together with the font code so as to discriminate KANJI. Then the KANA-KANJI conversion control part 22 decides whether or not the different type code is sent together with the font code. When it is decided that the font code and different type code are sent, the KANA-KANJI conversion control part 22 inquires of a font data management part 26 about whether or not different type font data is stored in a font data group 27. When it is made evident as a result of the inquiry that the data is stored, a display process similar to a case wherein the font code does not include the different type code is performed to determine a character string or perform reconversion processing.