This study was designed to evaluate the global scientific output in the ISI subject category of "water resources" for the past 16 years. Data were based on the online version of the Science Citation Index Expanded, Web of Science, from 1993 to 2008. Articles referring to water resources were assessed for many aspects, including distributions of source countries, institutes, words in the title, author keywords, and KeyWords Plus. The h-index was also calculated in terms of the characteristics of publications. Distributions of paper titles, the author's keywords, and KeyWords Plus at different periods were applied to evaluate research trends. The analysis showed that researchers paid most attention to groundwater and water quality parameters. Modeling and adsorption were the most popular techniques in water resources research. In addition, the relationship between the impact factor and h-index was significant for journals in the first group. The impact of the most cited articles each year were also discussed along with the article life information.