Dendrimer is a newly synthesized nanomaterial with natural nanometersize, unique monodispersion, and multifunctional surface groups.And all these unique properties have led to its wide use in biomedical domain, especially in targeted drug delivery.The drug molecules can be either encapsulated in the hydrophobic chambers inside the dendritic skeleton,or chemically conjugated to the functional groups on the surface of dendrimer. The multifunctional surface groups can be linked chemically to various target ligands, including monoantibody and its Fab fragment, folic acid, biotin, etc, which lead to the delivery of drugs to the targeted sites for targeted therapy. This article mainly discusses the application of dendrimers in targeted drug delivery and introduces the toxic property of dendrimer.