Abstract: In this paper, based on a ultrastructure level, structure changes of the tetrads, microspore, and tapetum during the development process of the microspore in Cunninghamia lanceolata (Lamb.) Hook are investigated. It shows that the tetrads are simultaneous type, cytoplasm of the microspore tetrds is extremely dense, metablism of cytoplasm is very active, and endexine is directly formed by the secretory substances of cytoplasm. The free microspores belong to the constricted stage and vacuolar stage respectively. Occurrence of the large central vacuole and rapidly increasing volume of the microspore are followed by the vacuolar stage. The tapetum has its own changes. Numerous endoplicates which form a "bayed-stracture" on the membranece occur during the free microspore stage. In the late development process of the microspore, there are a large number of myelin-like bodies and autophagia vacuoles. It seems that metablism is considerably active and changes of the cellular structure are conspicuous. The tapetum in Cunninghamia lanceolata narticipates in wall formatoin of the microspore.