The Jiangnan（江南south of the Yangzi River） urban’s forms originated from primitive village and settlement. We can find some building remains in Hemudu（河姆渡）, Majabang（馬家浜） and Liangzhu（良渚） cultures. With Wu‐Yue（吳越） economic development, the embryonic form of urban, such as the Wu‐Yue’s capitals, gradually came into being. Compared with the Centre‐China culture, the Wu‐Yue culture already had some distinct local characters. To the Han Dynasties（漢代）, especially after the middle time of East Han Dynasty（東漢）, the Jiangnan urban cultural character gradually became visible with the north bachelors coming into the south and the economic recovering. A group of literature families and aristocratic families grew up in this time. But compared with the Centre‐China culture, the whole effects still were weak. To the Three Kingdoms（三國） times, the Suns（孫氏） ruled East Wu（東吳） for many years, it leaded Jiangnan economic to further development. Since the Yongjia Chaos（永嘉之亂） broken out in the end of West Jing Dynasty（西晉）, the northern population flooded into Jiangnan, especially with the aristocratic families moved into the south, it brought Jiangnan economic and culture to deeply development. In this time, the economic and culture center started to be drifted forward to the south, the Jiangnan urban development obtained great space. It provided the people’s writing and criticism with material base and communication space. The urban planted some amorous and gorgeous characters in the literature. The urban scenery and the human activities became to be the focus as the earliest fusion point between urban literature and nature literature. All of literature criticism almost happened in the urban. With the development of Jiangnan urban, the Six Dynasties literature took place various new elements. So the conclusion can be arrived that the first mutual influences happened in the Six Dynasties（六朝）, not in the Tang Dynasty（唐代）, even not in the Song Dynasty（宋代） as the common folk literature researchers thought.