In temperate and boreal climate, the timing of plant's growth cessation in autumn highly affects plant carbohydrate reserves and ecosystem productivity. However, the abiotic and biotic factors regulating plant's autumn phenology remain poorly understood, especially on herbaceous plants inhabiting temperate grassland ecosystems. This study collected 10′533 of ground phenological observations conducted by professionals on 41 herbaceous species (26 for forb species and 15 for graminoid species) in 201 stations spread over China. With multiple regression analysis and contribution decomposition, we assessed the total and separate effect of preseason temperature, precipitation, sunshine hours, and spring phenology on leaf senescence and explored their relationships with species, plant functional types, and geographical gradients. Results show that leaf senescence has significantly delayed for 31% of the site-species. Sunshine hours, temperature, precipitation, and the leaf-out date primarily explained the variation of leaf senescence for 36.6%, 31.7%, 22.0%, and 9.8% of the investigated site-species, respectively. Further analysis demonstrated that sunshine hours were the foremost factor in controlling leaf senescence for 60.1% of graminoid species (n = 15) and temperature for 42.3% of forb species (n = 26). This suggests that light and heat primarily determine the autumn phenology of herbaceous plants, but there are great differences among species/functional types. Spatially with increasing altitude, we observed an increasing total explanation rate of four factors and a growing individual explanation rate of precipitation to leaf senescence. Overall, we not only highlight the key effects of sunshine hours and temperature on the autumn phenology of herbaceous plants but also emphasize the dependence of phenological responses on species, functional-types, and geographical gradients, which implies the complexity of modeling future autumn phenology of herbaceous species at regional and global scale.