A terminal displays icons (111) representative of actions / conditions of expression data, such as animation, sound, or text, on an icon palette (110). Further, on the terminal's display screen, there is provided a control input area (120) where icons (121) and text (122) are displayed in a mixture, allowing the user to input an icon (121) by selecting it from the icons (111) on the icon palette (110) and to input text (122) from a keyboard or the like. The terminal controls the actions / conditions of a character representing the user displayed in the animation display area (100a) based on input results in accordance with the icon (121) and displays the text (122) positioned immediately after the icon (121) in synchronism with the animated character representing the user. In this manner, an expression data control system is realized which is capable of quickly and correctly controlling various expressions, including subtle differences between them.