Urban green spaces (UGS), often metaphorically referred to as the “green lungs of cities,” play a crucial role in sustainable urban development and are a key element of land-use policy. This study evaluates the economic value conferred by UGS through urban parks, employing a Multi-scale Geographically Weighted Regression (MGWR) model within a hedonic pricing framework. By focusing on the localized impact of UGS on housing markets in developing megacities, this research utilizes Chengdu, China, as a case study to reveal spatial patterns in property valuations. The findings demonstrate a significant localized impact of UGS on housing prices, characterized by pronounced spatial heterogeneity. A substantial premium on housing values is correlated with proximity to urban parks, reflecting a high market valuation of these green spaces. This premium varies spatially, diminishing in more peripheral urban zones but still significantly influencing overall housing market dynamics. The study highlights the importance of reassessing rapid, policy-driven park expansions. There is a need for value-based UGS integration in sustainable urban planning, emphasizing strategic, ecologically informed decision-making that balances land development with conservation and meaningful resident engagement.