Abstract: Through investigation on water area and changes of water area since the 1950s in Jiangsu province, we evaluated the current situation of water area, and expounded the importance of researches on suitable water surface ratio. Based on research achievements of suitable water surface ratio at home and abroad, we put forward a new approach, analogy, to research the suitable water surface ratio in Jiangsu and its prefecture-level districts. Results show that suitable water surface ratio is around 17.30% and is proved to be reasonable. This approach provides reference for the research on suitable water surface ratio in similar regions or larger regions.

Key words: suitable water surface ratio, analogy, status of water area, Jiangsu Province