Water security is one of the key components of the national security of the Republic of Kazakhstan, given the limited water resources, their uneven distribution, and increasing environmental challenges. Under the conditions of climate change, urbanization, and industrial growth, the relevance of rational use and preservation of water resources is significantly increasing. The aim of this study is to conduct a comprehensive analysis of Kazakhstan’s water security issues, including the state of water resources, their use and management, as well as the legal framework and international experience. Various scientific methods were applied to achieve this goal. The historical and legal method was used to analyze legislation, including the Water Code and Environmental Code of the Republic of Kazakhstan, along with international conventions governing the use of transboundary waters. The analytical method identified key issues such as water pollution, uneven distribution, and low efficiency of water use. The system analysis method provided an integrated examination of social, economic, and environmental factors affecting water security. The comparative method contributed to studying international practices in water resource management and identifying best practices applicable to Kazakhstan. The research revealed major challenges for Kazakhstan’s water security, including limited and uneven resources, outdated infrastructure, pollution, insufficient funding, and unregulated use of transboundary water flows. The findings emphasize the need for infrastructure modernization, digitalization of water management, legal improvement, and enhanced international cooperation. Sustainable water management requires an integrated approach based on environmental protection, pollution prevention, and rational use of resources.