<p>Urban golf courses in the Republic of Korea are subject to stringent zoning regulations and land use restrictions, which has led to their long-term preservation in both urban and peri urban areas. While not designated as conservation zones, these sites have unintentionally contributed to the protection of adjacent forest ecosystems. This study investigates the role of urban golf courses in forest preservation and their associated air quality regulation services using a coupled approach: the SLEUTH model and the i-Tree Eco model. We simulated two contrasting land use scenarios: a preservation scenario where golf courses remain undevelopable, and a development scenario where golf courses are reclassified as general sports facilities. The results show that converting golf courses into developable land would lead to a loss of approximately 43% of the existing forest area, especially in urban fringe zones. Furthermore, i-Tree Eco simulations revealed that forests within or near urban golf courses accounted for over 60% of total CO and NO₂ absorption among all golf course zones, despite covering only 37.9% of the total golf course area. These findings suggest that urban golf courses serve as unintentional forest buffers and critical green spaces for air pollution mitigation, particularly in densely developed regions. We argue that ecological functions of such non-traditional green spaces should be more explicitly considered in land use planning, zoning policy and urban ecosystem service assessments. As cities continue to densify, leveraging existing regulatory constraints for ecological benefit may offer a practical strategy for sustainable urban development.</p>