Researches on input and output at home and abroad are divided into two parts. One part is about researches in application of the input-output table and the modeling techniques; the other is about methods of IO table or modeling research. Quite a number of application researches have been done in China, but within not so many fields as researches in other countries, although there are relatively more discussion and researches in modeling methods. The paper reviews the development of researches in input and output of water resources at home and abroad through the clues of extended modeling techniques and method updates, and discusses shortcomings and the development trend of researches in input and output of water resources. Because the IO table of water resources reflects the relationship between water resources and the economical structure, it is not an easy job for researchers to draw up such a table. The normal case is that researches in input and output of water resources are carried out with combination of study areas' IO tables and other models. Modeling techniques of input-output of water resources have advantages to solve structural problems. It excels in solving problems of the industrial structure, distribution structure and consumption structure of water resources. But with high degree of presupposition, the techniques can only be utilized to make annual modes owing to datalimitation, and this further exposes inflexibility of modeling techniques of input-output of water resources. So it is necessary to do some modification to models in the actual application. Three types of extended modeling techniques of input-output are formed by combining extended modeling techniques of input-output of water resources respectively with local IO tables, supply of water resources and extended tables. Because there must be a lot of input of human power, materials and time for formulation of an IO table, it is neither possible nor necessary to draw up such a table each year. Even in the year of table formulation, publication of IO tables will usually lag behind for two to four years. Therefore, lack of timeliness has been always one of the main bottlenecks to influence researches in IO models, and researches in techniques of upgrading and establishing IO tables are generally much valued. Nowadays, the upgrading methods have developed from the method with unchanged consumption coefficients and scaling methods like RAS to multiple methods. With the improvement of computing methods and appearance of a large number of computer software targeted at nonlinear programming problems non-linear optimization models, non-linear optimization models are greatly used. In summary, the existing methods to upgrade IO tables are mainly statistical methods, optimization methods and analytical methods of macro-economy. Based on input and output of water resources, one of the hot research areas in ecological economy, the paper summarizes problems existing in the current researches in input and output of water resources and issues needed to be further explored after all-round review. Researches in input and output of water resources are gradually deepening in data utilization and research focus. But there exist shortcomings and deficiency for the method of input and output of water resources. New researches in framework design and relationship between water resources and economic growth and expansion of research background will not only open up new areas of researches in input and output of water resources, but gaps will also be filled in China's researches in input and output of water resources.