Index of Biotic Integrity (IBI) is a quantitative index which is used to measure the ability of aquatic biocoenose to maintain the steady state of species composition, diversity,structure and function.IBI has been gradually developed in recent 30 years and become one of the most important indices to quantitatively assess the aquatic ecological health.IBI is a numerical measure which is got through recombinating multi metric index from different sensitivities, whose theoretical foundations are ecology and mathematics, and involving biology,environmental science and other disciplines.IBI, as a quantitative analysis method, its theoretical and technical system is still developing and evolving.The key technology is the selection of the reference site, the selection of measurement indicators, the empowerment and recombination of index.The realization of each link has many viewpoints and methods.Based on forecasting model research of a large amount of monitoring data is a hot research topic at present,but there is no research reports of the IBI forecast model in the Chinese academic circles.Except the traditional F-IBI, B-IBI, A-IBI, P-IBI and AP-IBI, Some scholars have proposed M-IBI which will become an important research direction in the future based on the above research results of s-IBI.The purpose of the application of IBI can be divided into the quantitative analysis of the water ecological health, the quantitative analysis of the disturbance response of water, and the prediction of the water ecological health.The article points out that IBI is based on 3 hypotheses to evaluate the ecological health of water, and when the ecological damage is serious or the ecosystem is in a dramatic change, IBI doesnt work.Also, the article summarizes the characteristics of IBI..quantitative, object dependence, discipline crossing,standardization trend, systematic errors.The article discusses that IBI is a promising method in the field of rural river, irrigation districts and farmland ecological health evaluation.