Background/Objectives: This study assesses agricultural sector competitiveness in South Korea, New Zealand, the United States, and China, considering global challenges like food security and sustainable development. Methods/Statistical Analysis: An enhanced double diamond model, based on Porter's model, and the entropy method were utilized to evaluate competitiveness across selected countries. Findings: Distinct strengths were observed in each country within the adjusted double-diamond model. The US and New Zealand excelled in factor and demand conditions. China outperformed South Korea in demand conditions and related industries. Improvements/Applications: This research provides insights for policymakers in enhancing sustainability and competitiveness in South Korea's agricultural sector. It also highlights opportunities for stakeholders to improve efficiency and governance through digital transformation.