Abstract: Uneven spatial and temporal distribution of water resources is widely existed. Building reservoirs is one of the most effective means to regulate water resources. In China, more than 90 000 reservoirs of various kinds have been built. In order to maximizing the engineering benefits and water security capability of reservoirs, comprehensive, accurate and georeferenced attribute datasets of reservoirs and dams at national and global scales are urgently needed including location, boundary, height, storage capacity and function. During the past decade, several reservoir and dam data sets have been published and significantly advanced the large-scale researches on the environmental impacts of reservoirs and dams. However, there are significant discrepancies in the numbers and values of attributes amongst data sets. Therefore, it is urgent to carry out comparative assessment and to identify the future direction of these data sets. In this study, main contents of the present publicly available reservoir and dam data sets were introduced, data sources of reservoir and dam information and the production procedures were summarized, and basic georeferenced attributes were compared amongst different data sets including location, classification, boundary, etc. More importantly, the spatial distribution characteristics and statistical differences of each data set in China are compared comprehensively. Problems such as timeliness of data set, repeated definition of reservoir and lake, and difference of reservoir area are also explored. Moreover, urgent and important research issues related to such data are reviewed, such as flood control, power generation and irrigation benefit of reservoirs, hydrological, carbon and interception effects of reservoirs and dams, and river habitat fragmentation, etc. Finally, the future production and application of dam and reservoir data sets are discussed. It is found that present data sets contain more large reservoirs and less mall reservoirs, and large reservoirs have comprehensive attributes, while small reservoirs have insufficient attributes. There are also many other differences between different data sets. In the future, it is necessary to further improve the data records of reservoirs and dams and coordinate the differences of data sets to achieve complete simulation of reservoirs and dams.