Abstract: Urban parks can play the role of “cooling islands”. A comprehensive understanding of the cooling benefits of urban parks can effectively alleviate the urban heat island effect and improve the adaptability to climate change. Taking 25 urban parks in Nanjing city as the research object, this paper conducted a comprehensive study on the cooling benefits of parks with two maximum impact indicators of park cooling area, cooling efficiency and two cumulative impact indicators of park cooling intensity and cooling gradient. The results showed that: (1) The urban park had a significant cooling effect, by reducing the ambient temperature by 0.16 ℃-2.28 ℃. (2) The correlation analysis showed that the park cooling area was significantly positively correlated with PP, PA and NDVI, and the park cooling efficiency was significantly negatively correlated with PP, PA and LSI. The cooling intensity and gradient were positively correlated with NDVI, PP and PA. The correlation between the four cooling indexes and MNDWI was not significant. (3) Different cooling benefits were shown for different types of parks. Special parks or community parks were better fitted to the areas of tight land use. Construction of comprehensive parks should take more consideration of complex boundary conditions and vegetation conditions to maximize the cooling benefits. This study was expected to guide the construction and optimization of urban parks in the future, to effectively respond to the urban heat island effect.