The science–policy connection for informing authority’s planning process has been considered weak and inadequate in China’s spatial planning system (Y. Yang et al., 2020). This study proposes a practical approach for planning GI networks by considering on both the connectivity of natural habitats for preserving biodiversity and the multifunctionality of these areas by delivering of multiple ecosystem services. The outcome can be used as a base map of GI plan at the regional scale and it can also give instructions for spatial planning at the urban scale. As China is finalizing the redline system for vital environmental protection and controlling the extent of urban expansion, our approach can be regarded as a bottom-line strategy that involves the aspects of ecological sensitivity and suitability. Because urbanization is essentially irreversible within human lifetimes, it is of great significance to safeguard key ecological sources and corridors in advance to assure the long-term provision of crucial ecosystem services (Hou et al., 2022). Our proposed method for identifying key locations for GI planning is applicable not just to highly urbanized regions, but also to rapidly urbanizing regions.

•Both concepts of connectivity and multifunctionality are considered in GI optimization.•Four important ecosystem services are spatially quantified and mapped.

•Prioritized spaces for GI optimization are identified.

•The proposed approach can be used for regional GI plan globally.