Abstract:The ultrastructure of microspore development in Jatropha curcas L. was observed under transmission electron microscopy. Many endoplasmic reticulums and plastids are present at microsporocyte stage. Organells including endoplasmic reticulum, mitochondria, plastids, dictyosome and sphaeroplassts are rich in microspore at meiosis and tetrad stages. And mitochondria and endoplasmic reticulum are still abundant during early and late microspore stages. The microspore divides into a large vegetative cell and a small generative cell. The vegetative cell abounds with starch grains and the generative one is rich in lipids. A great number of starch grains occur in epidermis, endothecium and middle layers at microsporocyte and tetrad stages, and are remarkably reduced at microspore stage. The tapetum is rich in organells from microsporocyte stage till late microspore stage, mainly including endoplasmic reticulum, plastids and mitochondria. Starch grains and lipids supply nutrients for the pollen development.