If we see internet as ＂the fourth media＂ that rises after the other three traditional mass medium - newspaper, broadcasting and TV, we can also see blog as ＂the fourth internet conversational tool＂ that rises after the other three traditional internet conversational tools-email, bbs and icq, because blog has much more characteristics than the traditional mass medium. Ideological and political education workers are guard of the ideological domain. So they must not neglect the effect of this important disseminative tool.