Abstract
Originally, nanqu (literally "Southern Songs",南曲) and beiqu (literally "northern Songs",北曲) have their own features of regulations and styles. After the middle of the Yuan Dynasty (元代,1260-1367), beiqu spread to the southern lands. Beiqu and nanqu influenced each other in respect of regulation, composition, singing method, etc.. This essay investigates if the tunes of nanqu have been influenced by beiqu (南曲北化) or the tunes of beiqu influenced by nanqu(北曲南化). This essay chooses the changes of "the rules of tunes", "the composition of tunes" and "the music of tunes" as the entering point of discussion. The qingjiangyin (【清江引】) represents the tunes of beiqu which have been affected by nanqu; the pudenge (【撲燈蛾】) represents the tunes of nanqu which have been affected by beiqu. There are only a few tunes to have been affected; however, these tunes give clues of interaction between nanqu and beiqu. Through these tunes, we can also explore the possible transitions of tunes, and the relationship between the poetry and music of the tunes.