The authors highlight features of the extralinguistic information that are important in terms of methods to teach the Korean language to Russian-speaking students. A task was set to develop an appropriate teaching system that considers the non-obviousness of availability of extralinguistic information, which is necessary for students to communicate in a foreign language, and also considers the non-linguistic nature of this information and the difference in its scope as a teaching subject depending on the level and profile of the educational institution. Stages for researches aimed at the settlement of this task are indicated. Concepts of “extralinguistic information”, “lexical background”, “background knowledge”, “background information” are compared, and their socio-cultural conditioning by context, as well as a methodologically important distinction between the concepts of “information” and “knowledge” are emphasized. Accordingly, a number of conclusions are made about the methodological significance of separating such information into long-term and short-term, about fluidity of the teaching content and about necessity to correct it promptly. It is noted that it is important for teaching communication to gain the ability to reveal the implicit, which is based only on sufficiency or insufficiency of relevant information. The authors attempt to classify and structure the scope of extralinguistic information, on the basis of which students form their background knowledge, using a notion of “information reserve” developed in the frame of translation theory. A methodically significant difference in the scopes of “extralinguistic information” depending on a degree of such reserve is shown on specific examples. It is shown also that the scope of accumulation of extralinguistic information at a certain level of teaching can vary. The conclusion was made that “extralinguistic information” cannot always be represented and, therefore, should not always be presented exclusively in the verbalized form. The authors highlighted the groups of relevant issues as to determination of how to convey such information during teaching and marked out the methods to form and to interpret the corresponding associations and images in the process of teaching Korean language.