Abstract: Chinese in the Wei，Jin，and the Southern and Northern Dynasties is the main part of mediaeval Chinese. Researchers have made many achievements in studies about grammar of this period，but achievements are slightly insufficient in conjunction study. Through a comprehensive analysis on research results of Chinese conjunctions in the Wei，Jin，and the Southern and Northern Dynasties，we can find that the previous researches are mainly synchronic descriptions but not diachronic interpretations of the origin and evolution of newborn conjunctions. Therefore，carefully analyzing conjunctions in this period，and discussing the rules that lead to the emergence of newborn conjunctions from the perspective of diachronic evolution，have apparently been a field of research which needs to be strengthened.

Key words: Chinese in the Wei, Jin, and the Southern and Northern Dynasties, conjunction, grammar history, synchronic description, evolution interpretation