This article is written with a view to determine the place and function of plural form “siz” and “siler” in the polite way of treatment. Why the words “siz” and “ siler” are used in plural form when people address to estimable and elder people.In this article we try to answer the question above. At the end of investigation we came to a such conclusion: Turkic languages have their own prediction of using “siz” and “ siler” in the polite form of treatment in comparison with the version which was offered by European researches. Turkic languages deny the use of “siz” and “ siler” which were used in official decree in Rome civilization in order to reveal the person who occupied a high post. But in Turkic languages as well as Kyrgyz language “siz” and “ siler” were used in order to widen the meaning as well as “siz” and “ siler” were used by the leader who was at his tribe’s post in his addressing to old people.