The stomatal characters of dominant grassland species in the Tibetan Plateau and Inner Mongolia Plateau were investigated by using plant microtechniques. We aimed to disentangle the stomatal characters and their relationships with environmental factors and reveal the adaptation strategies in two types of stomatal apparatus, which are composed of kidneyshaped and dumbbellshaped guard cells. The results showed: (1) the coefficient of variation of stomatal characters of dumbbellshaped stomatal apparatus was smaller than that of kidneyshaped stomatal apparatus. (2) The relationships between stomatal characters of dumbbellshaped stomatal apparatus and environmental factors were weaker than that of kidneyshaped stomatal apparatus. (3) The environmental factors showed different effects on the adaxial and abaxial stomatal characters in dumbbellshaped stomatal apparatus, while in kidneyshaped stomatal apparatus there were no different effects on the adaxial and abaxial stomatal characters. (4) The stomatal characters were closely correlated to precipitation in dumbbellshaped stomatal apparatus, while in kidneyshaped stomatal apparatus they were closely correlated to temperature. (5) The stomatal characters of the same stomata had significant differences in the two regions (Tibetan and Inner Mongolia Plateau). We came to the conclusion that there were significant differences in stomatal characters and the relationships with environmental factors between kidneyshaped and dumbbellshaped stomatal apparatus. The results indicate that it is necessary to distinguish the types of stomata when analyzing stomatal characters, and will be helpful for further understanding the adaptation strategies of leaf stomatal characters of grassland plants in China under the background of global climate change.