1. A method of recommending a responsive sticker by use of a server that is connected to a first user terminal and a second user terminal through a network and relays an utterance inputted to a messenger between the first user terminal and the second user terminal, the utterance including at least one of a text and an image, the method comprising: generating dialogue situation information by analyzing a last utterance of a second user of the second user terminal and a previous utterance of the first user terminal, as the last utterance of the second user terminal is inputted into the server, the last utterance of the second user including a text type of dialogue contents, wherein the previous utterance of the first user is an utterance input to the first user terminal prior to input of the last utterance of the second user to the second user terminal; determining a similar situation from a dialogue situation information database that is already collected and constructed, using the generated dialogue situation information; selecting a responsive sticker candidate group from the determined similar situation; analyzing a relation between the first user and the second user based on the last utterance of the second user and the previous utterance of the first user; and recommending at least one responsive sticker of the responsive sticker candidate group to the first user terminal, wherein the step of recommending comprises selecting the at least one responsive sticker, from among the responsive sticker candidate group, according to propriety of the at least one responsive sticker in view of a type of the relation between the first user and the second user.