In a network conference system, a promoter terminal 10 has: a speaker selecting section 12 which selects the promoter terminal 10 itself or one of participant terminals 20 and 30, as a speaker terminal which is used by a speaker who makes an announcement in a conference; and a usage function controlling section 13 which, in accordance with a result of the selection by the speaker selecting section 12, controls the speaker terminal and the terminal other than the speaker terminal so that a predetermined application is available only in the speaker terminal. Further, method for using the network conference system is provided.