Jatropha curcas is considered as a potential biodiesel feedstock plant. To date, however, it remains a semi-wild species. Transgenic modification is one of the most effective and rapid approaches to accelerate its breeding process. Various methods of genetic transformation, such as Agrobacterium- and particle bombardment-mediated transformation, have been attempted and improved over the past 10 years. This chapter presents a comprehensive account of the influence of several important factors on the genetic transformation of Jatropha. It also introduces studies on transgenic Jatropha involving functional genes for novel agronomic traits, including plant morphology, flowering time, seed development, seed oil content, oil composition and yield, as well as biotic and abiotic stress tolerance. Moreover, improvements in genetic transformation and the completion of genomic sequencing analysis give Jatropha the potential to become a new model species for studies on gene function and genetic improvement in woody plants.