Parking and parks are both crucial to downtown economic development. Many studies have shown that downtown parks significantly contribute to increasing surrounding property values and attract residents, businesses and investment. Meanwhile, sufficient available parking promotes accessibility to downtown that also contributes to increasing tax revenue for local government. However, both downtown parks and parking raise problems. Many downtown parks have become places for drug dealing, shooting and vandalism since the decline of downtowns in the 1960s. At the same time, residents and visitors alike oftentimes complain about the lack of parking while in fact parking spaces occupy a large amount of land in downtown. Parks and parking also compete for space in downtown where land value is higher than the rest of the city. To address these issues, several cities have begun to address the relationship between parking and parks by placing them in one place: park on the ground level and parking underneath. This typology is defined as a park-above-parking project in this research. However, this phenomenon has received little scholarly attention. To justify the existing situation of park-above-parking and to contemplate future projects, this research provides a spatial-based investigation to discuss the empirical relationships between social cultural and political-economic impacts, design quality, and related policy-making processes based on four cases. A longitudinal study that traces the direct and indirect impacts of park-above-parking projects was conducted for each case through both qualitative and quantitative methods. This research provides a set of methods for the measurement of contributions of park-above-parking downtown, connections between park quality, social use and adjacent economic growth, recommendations for land use planning policy-making and guidelines for the design of park-above-parking projects.