This research examines the impact of the Grand Ethiopian Renaissance Dam (GERD) crisis on regional security within the Nile Basin, focusing on Egypt and Sudan as the most affected downstream states. The study analyzes the hydrological, political, and economic implications of the dam and highlights how the absence of a binding legal framework increases risks related to water security and regional stability. It evaluates potential filling and operation scenarios and their consequences for food security, energy supply, and power dynamics in the region. The research also explores the strategic options available to Egypt and Sudan, including diplomatic engagement, regional cooperation, and alternative water management policies. The study concludes that the GERD crisis represents a complex regional challenge requiring comprehensive management and coordinated strategies to reduce escalation risks and promote long-term stability. Keywords: GERD, regional security, water security, Egypt, Sudan, Nile Basin.