This article is from the grammatical point of view, to explore the usage of the 88 ”Yan” words in ”Analects of Confucius”. ”Analects of Confucius” ”Yan” word purely as a modal particle and virtual into the endings are few clear examples, the The Analects ”Yan” word more than half of a half of ”usage of the word”; Secondly, the study found that: ”Yan” word of the ancient Chinese have gradually differentiation and maturation of semantic forming laying today Chinese ”Yan” word usage.