The study focuses on understory ground cover plants in Shanghai parks, where sample plots were randomly selected from understory zones with aesthetically pleasing landscapes. The canopy closure of each plot was measured to identify suitable ground-cover species and optimal configuration patterns across different canopy-closure levels. A total of 154 understory ground cover plant species were documented, with 37 species demonstrating robust shade tolerance and suitability for understory conditions where canopy closure is 0.9 or higher. Among them, 27 species exhibited a broad ecological amplitude. Most flowering plants showed optimal fl owering performance under canopy closure below 0.8. The confi guration patterns of understory ground cover plants emphasized spatial hierarchy and ornamental longevity, comprising six planting arrangements: mass planting, strip planting, color-block planting, fl ower-border planting, uniform mixed planting, and free scattering. Strategies such as diversifying understory plant species, promoting the use of innovative, high-quality ground cover plants, scientifi cally selecting adaptable varieties based on upper-layer canopy closure, and refi ning plant confi guration patterns are recommended to further improve the understory landscape eff ect of green spaces in Shanghai parks.