The development of photography technology has changed the domain of fashion illustration that once prospered while the improvement of computer technology can now reedit the limits of photos. Presently, the border between photography and illustration has been collapsed through a medium of computer. And this phenomenon tends to be encouraged by expressive features that traditional fashion illustration was characterized by. Thereupon, this study aims to investigate the expressive features of drawing lines in clothing on the 20th century fashion illustration based on such periodic demand. Therefore, this paper deals with the followings: the first is to understand the concept of the drawing line in clothing ; the second is to consider the features of drawing lines in clothing on the Eastern and Western paintings; the third is to figure out the flow of the 20th century fashion illustration; the fourth is to analytically study the features of drawing lines in clothing shown on the 20th fashion illustration.