[Objective] With the rapid economic and technological development in China, information technologies, such as big data and cloud computing, are being employed for the construction management of hydraulic engineering projects. However, the unbalanced technological development and the disconnection between information technology and the actual construction process still exist. Thus, exploring the research and development in the technological field is crucial. Previous studies have examined the development status of specific information technology in hydraulic engineering informatization. However, research and development status were not systematically demonstrated using quantitative analysis. Patents are critical technological achievements for hydraulic engineering informatization, providing comprehensive technical information for technological exchange and innovation. This research aims to reveal the technology layout and prospects in hydraulic engineering informatization from the patent analysis perspective. [Method] This study proposes a text mining-based patent analysis method to examine the patents on hydraulic engineering informatization collected from the IncoPat global patent database. Initially, the patent application trend, application regions, applicants, and international patent classification (IPC) codes were explored through descriptive statistical analysis. Subsequently, a word frequency analysis was conducted on patents' titles and technical efficacy, and word clouds were drawn to preliminarily observe their primary themes and functions. Furthermore, text mining was utilized for clustering patent topics. The topic intensity and evolution characteristics of different categories of patents were analyzed based on the clustering results. [Results] Results show that China has entered a period of technological development since 2013, and the number of patents has increased rapidly since 2019. The patent applicants are mainly in provinces where enterprises, universities, and research institutes are concentrated. Enterprises and individuals apply for 77.8% of the patents and emphasize the application value of technology, whereas universities and scientific research institutes contribute to 24.2% of the patents and place great importance on technological innovation. The IPC codes of these patents mainly include hydraulic engineering (E02B), data processing system or method (G06Q), electronic digital processing technology (G06F), and hydrological information monitoring (G01F), revealing interdisciplinary characteristics. The latent Dirichlet allocation (LDA) topic model divides the patents into nine technical topics corresponding to four application categories. Among these categories, the number of patents for "equipment and hardware" is the largest and rapidly increasing, indicating promising development prospects for related technologies. Next, the "comprehensive management system" serves as a crucial integrated application, with steadily improving research and development in recent years. In addition, patent applications for "information monitoring" show an increasing trend overall, but few aim to monitor the construction process, indicating that construction monitoring should be considered an important direction in future research. Moreover, the number of patents for "data analysis" has been low for a long time, reflecting the urgency to improve the data analysis ability of construction management in hydraulic engineering projects. [Conclusions] These findings systematically reveal the technology layout, development status, and application prospects of hydraulic engineering informatization in China, providing research method support and empirical reference for future technology development and patent application. This study also recommends improving the capability of construction monitoring for realizing the overall perception system, promoting the application of big data analysis in the construction management of hydraulic engineering projects, and encouraging industry-university-institute collaboration. © 2023 Press of Tsinghua University. All rights reserved.