The Korean Peninsula faces significant seasonal and regional variations in precipitation, and the irregularity of rainfall due to climate change poses a growing challenge for water management in both South and North Korea. In response, the two countries have developed distinct irrigation approaches shaped by differing institutional and technical conditions. This study provides a comparative analysis of irrigation systems, earthen canal structures, and operational frameworks in both Koreas, focusing on differences in canal design standards, slope ratios, and lining methods. South Korea utilizes standardized guidelines, concrete-lined canals, and slope stability analysis, while North Korea relies on gravity-flow earthen canals adapted to topography and limited resources. Key findings highlight differences in cross-sectional design criteria, canal shapes, and lining materials such as mud, concrete, and synthetics. North Korea emphasizes simple excavation and embankment techniques, whereas South Korea applies systematic earthwork planning and long-term maintenance strategies. This study offers insights for future inter-Korean cooperation by identifying complementary design principles and water management strategies. The results may support joint policy development and the construction of efficient, sustainable irrigation infrastructure across the Korean Peninsula