This study aims at suggesting ways to establish text typing of writingdomain in Korean language education based on ecology. It is originatedwith critical mind that an existing text type of writing domain could notinclude an authentic writing which deals with learners’ ecological life, becausethose text type has a fixed text typing logic. So this study has a premise that the text of writing domain closely relatesto learners and their environment and maintains the wholeness, andthe text typing of writing domain would be set by these premise. At thispoint, a study about the relationship and wholeness is “ecology” and thecore competence of ecology is “sustainability literacy”. It is a new attemptto establish text typing discourse of Korean language education, that is,the text typing logic based on ecology focusing sustainability literacy. Concretely, writing text features considered with writing competencefocused on sustainability literacy follows those three expanded directions. Maximization of the genre dynamics in “text as a mode”, actualizationof text strategy by ideal writers in “text of professional writers”, emphasizingtext writing of a self-life, especially self-examination in “text oflearner writers”. Followed by these facts, “the text typing standard in Korean languageeducation” would be critically considered for concentrating the text typingdiscourse. As a result, the text typing standard in Korean languageeducation needs a “complex text typing”. But a standard of that complextext typing could be sincerely considered. Ultimately, to have those text typing standard, this study adopts two concepts of “ecological language learning”, “affordance” and “emergence”. And these two concepts connect to two faces of sustainabilityliteracy, the text type of writing domain could be established, “writingtext of social relationship” and “writing text of existing awareness”. Thesetwo types have subtypes, the former includes “information delivery, persuasion,friendship, emotion expression” as “writing of register”, and thelatter includes “past-present, present existence, present-future” as “writingof enjoyment”.