The three-dimensional morphology was studied and the dynamic morphological changes in the process of losing water of stomata on the leaf of cabbage mustard were observed by using the tapping mode of atomic force microscope (AFM). The results showed that stomata and the other surrounding cells, including guard cells, subsidiary cells, and epidermal cells, could be clearly imaged by AFM. Furthermore, the micro fibers was found covering the subsidiary cells with diameter of about 400 nm with interval about 200 nm.