The article deals with the set of grammatical notions used by the author of 《语助》 “Yuzhu”, that is the first special monograph in Chinese linguistics dedicated to the description of function words. The study of works significant for the development of the linguistic knowledge is very important for historiographical and epistemological description of the formation of a certain tradition (in this case the Chinese one), since such works mark the stages of qualitative shifts in the structure of knowledge. In the course of the research three types of function words were singled out: 辞 ci, 声 sheng and 语助 yuzhu. The description of how these terminological units are used in the works preceding 《语助》 “Yuzhu” (such as 《礼记正义》 “Li ji zheng yi”, 《毛诗故训传》 “Mao Shi gu xun zhuan”, etc.) is given. Diachronic analysis shows a certain continuity of Lu Yiwei’s 卢以纬 interpretations: he does not offer his own variants of naming function words, but uses terms that were coined by the literary people and commentators in previous epochs. To illustrate different types of function words, excerpts from dictionary entries are given, they are translated into Russian by the author. It is emphasized that these units do not have such properties inherent for terms as definition, accuracy of meaning, single meaning and form stability, so it is impossible to consider such units as proper terms. It is concluded that the traditional stage of linguistic knowledge development in China is characterized by the formation of the system of grammatical notions, there was no consistently developed terminological apparatus in this period, the structure of the language was not viewed systematically.