Abstract:The localization of ATPase in developing pollen grains of Lattuce sativa L. was studied using lead precipitation. ATPase precipitates（ppts）were present in the microspore cell during the early tetrad stage. Ppts then occurred largely in the inner pollen wall until shortly before pollens formed. At the late microspore developmental stage, abundant ppts were found specifically at the germ pore and in the large vacuole of microspore. During two-celled pollen grain stage, they were accumulated on the wall of the generative cell. After the generative cell came into the vegetative cell, ppts largely disappeared. Ppts were less in the generative cell than in the vegetation cell during the differentiation of the generative cell. However, they were more in sperm cells than in the vegetation cell after pollen formed. It is suggested that the distribution of ATPase is closely related to events of pollen development.