Guided by the policy of “Strengthening areas of weakness of water conservancy project and promotingsupervision of water conservancy industry” in China, the main keynote of reform and development of water resources in Jiangsu Province is “Strengthening area of weakness, promoting supervision and improving quality and efficiency”. By comparatively analyzing the basic data of the input into water conservancy and the investment of fixed assets at the corresponding period, the fiscal revenue and the GDP in Jiangsu Province from 1991 to 2018, it is shown that the water conservancy investment and financing system with the input mainly from public finance, fully play of market financing and extensive participation of social capital has been preliminarily formed. However, there are still some problems, such as the decrease of relative input intensity of water resources, the singleness of investment structure and the need of improving quality and efficiency. From the perspective of simultaneously increasing quantity and improving quality of strengthening areas of weakness, the water conservancy investment and financing system in Jiangsu Province should be improved through two ways: striving for the greater water resource investmentand improving the quality and efficiency of investment and financing system. Accordingly, the fund demand of “strengthening areas of weakness, promoting supervision and improving quality and efficiency” of water resources in the new period is better guaranteed, and the high-quality development of water conservancy in Jiangsu Province is achieved.