In the context of global warming and exacerbating extreme heat events, optimization of greenspace has become a nature-based solution to effectively regulate regional thermal environment. Deeply understanding the processes, characteristics, and the regulating role of landscape of the cooling effect of greenspace is important for optimizing the spatial structure and pattern of green space. For such proposes, the current theories, methods and cases related to the cooling effect of green space from the perspective of landscape regulation are sorted out. The key cooling processes of vegetation are reviewed at first. Vegetation achieve cooling effect through the processes of shading, evapotranspiration, carbon fixation, and turbulent flow directly or indirectly, which are also affected by the climate background related to atmospheric and soil water content, ambient temperature and wind systems. The cooling range, cooling intensity, cooling gradient and cooling efficiency from the internal perspective (the effect of greenspace landscapes on the local temperature) and the external perspective (the effect of greenspace landscapes on temperature outside the region) are summarized. The cooling effect from the internal perspective is mainly quantified by simulating the impact of land cover changes (such as afforestation, conversions of vegetation types) and fractional vegetation cover changes in the region, while the cooling effect from the external perspective emphasizes the relationship curve between the distance changes centered on the greenspace landscape and the corresponding temperature series. The spatial differences and key thresholds of above-mentioned measurement indicators are also discussed in this review. Furthermore, we focus on the approach of landscape regulation on the cooling effect of greenspace in details, and demonstrate the divergent impact of greenspace landscape components (typology, structure and size of landscape) and spatial configuration (spatial morphology and connection of landscape) on cooling effect. Previous studies have shown the dependable correlation between landscape components of greenspace and temperature, but the key thresholds are various in different regions with distinct climate and socio-economic development. The extent where regular or complex greenspace, agglomeration or discrete greenspace affect regional thermal environment are not consistent, but the influence of spatial configuration on cooling effect is usually weaker than that of landscape components. Eventually, according to the framework "mechanism-threshold-optimization", we proposed that studies on the cooling effect of green space from the perspective of landscape regulation need to concentrate on several key topics in the future, i.e., non-linear processes of cooling effect, regulating mechanism of greenspace for multi-targets synergy, and greenspace networks for improving cooling effect.