Abstract: 1. The ATPase activity in the spike-stalk cells of wheat was obviously localized at plasmallemma and the surface of cell wall bordering the intercellular spaces and their inclusions. The reactions of ATPase activity at chromatin and nucleoli were usually insignificant, and they were not found in vacuoles and other organelles (Figs. 1, 2, 3, 5, 6 and 7). 2. Three significant differences were observed between the middle part and the basal and upper part of the spike-stalk in wheat. (1) A large amount of inclusions were shown in the intercellular spaces of the middle part, and the high ATPase activity was seen at these inclusions (Figs. 6 and 7), but both they were seldom to be found in the intercellular spaces of the basal and upper part (Figs. 2 and 3). (2) The plasmodesmata of the middle part ceils was more than that of the basal and upper part ones (Figs. 1, 3 and 5). (3) In the middle part cells of spike-stalk, the cytoplasmic material was vigorously and actively transferred through the wall pores, and at the same time, the high ATPase activity was exhibited on the transferred cytoplasm (Figs. 4, 8 and 9). In addition, it was also observed that the cytoplasmic material entered into intercellular spaces from adjacent cells (Fig. 6). But it was hardly to see this phenomenon in the basal and upper part of spike-stalk. 3. It was discussed that the ATPase activity and the passage for material transport may play the role in transferring materials into the spike and they might be related to the development of the wheat spikelets.