This thesis has established models of water footprint in the Eco-industrial Park. The model was presented in three different levels, namely the level of Eco-industrial Park, the level of enterprises and the level of products. There are two parts of each model. The first part is the schema tization of different components of the water footprint. The second part is the mathematical model of water footprint counting.   After the models, we made several case studies using these m odels established in this thesis. The first case is the water footprint assessment of the Yixing Economic Development Zone (YEDZ). There are water footprints of the YEDZ in the year of 2009, 2012 and 2015 separately, which are 6787613.6 10 × m3,  61110018 10 × m3 and 62413749 10 ×  m3. Considering the different scales of the YE DZ, for example, the increasing industrial production and economic development, we also make the water footprints per capital of the YEDZ in the year of 2009, 2012 and 2015. The results are 19690.34 ×103m3/capita, 24667.07 ×103m3/capita and 48274.98 ×103m3/capita.  In the level of Eco-industrial Park,  we take several enterprises as case studies. The enterprises are within different types of industries including Chemical industry, Textile and dye ing industry, Optoelectronic industry, and Mechanical, Photovoltaic industry and machinery manufacture industry, etc. These enterprises are investigated by surveys and statistical documents. From  the results, we can see that the enterprises with big footprint are mostly in Chemical industry, Textile and  dyeing industry and Photovoltaic industry.  In order to make the data more reasonable, we also calculated the water footprint per unit out-put value. What’s interesting, the enterprises in Chemical industry, Textile and dyeing industry and Photovoltaic industry also have big water footprint per unit out-put value.  In the level of product, we take the surfactants produced by Jiangsu Guanyang Fine Chemical Co., Ltd. This enterprise has moved to a new place and made some improvement in the production. On one hand, they have increased the scale of production for three times than before; on the other hand they have adopted a lot of water saving facilities and measures, such as the use of rain wa ter, the increase of water recycling and the involvement of water cascade utilization. So in this thesis, we comp ared the water footprint of surfactants before and after moving. The Water Footprint of surfactants per year before moving is 22914.8(m3), after moving is 56804.4 (m3). However, the Water Footprint of surfactants before moving  is  2.52 (m3/t), while after moving is 2.08 (m3/t).  Finally, we gave some response options after the analysis and discussion of the results. The suggestions are given in three levels as well. The first one is to the gov ernment or so-called policy makers; the second one is to the enterprises; the third one is to the staff members in the Yixing Economic Development Zone.