To deal with global warming and energy shortages, the nuclear power industry has flourished in China. Operation of a nuclear power plant consumes a large amount of water and discharges radioactive wastewater into nearby water bodies. Therefore, assessment and management of water resources are crucial for such projects. This article proposes the contents, procedures and methods of water resources assessment for nuclear power plants in China. Taking a pioneering inland plant as an example, a case study was also developed. It was suggested that assessment of water resources for a nuclear power plant in China should focus on regional water resources analyses, rationality of water-draw and water use of a plant, feasibility of water sources and impacts of water-draw and wastewater discharge on regional water resources. The proposed processes mainly included site survey and data collection, work outline completion and approval, water resources assessment, assessment report completion, expert consultation and public participation, and technological review, as well as administrative approval. The methods presented were referring to legal documents, site survey, model simulation, expert consultation and public participation. Finally, suggestions, including comparing and selecting several optional sites, improving impact assessment of radioactive wastewater discharge and enhancing public participation, were also proposed.