Abstract: Biosynthesis of nanomaterials, as a novel “green synthesis technology”, has attracted increasing interests. Many microorganisms such as bacteria, actinomycetes (eukaryotes), as well as yeasts and fungi (prokaryotes) have been found to have ability to biosynthesize nanomaterials intracellularly or extracellularly. A series of metal and semiconductor nanomaterials with the excellent features of high monodispersity, stabilization, adjustable size, and biological activity, such as Au, Ag, Au-Ag, Fe3O4/ Fe3S, Titanium and CdS, CdSe, and Silica, have been biosynthesized. Here, we provided a brief overview of the current research on the use of microorganisms in the biosynthesis of nanomaterials. The biological procedures, biosynthesis mechanism, controlled biosynthesis on the shape and size, and their applications were summarized. The prospects of biosynthesis using microorganism have also been addressed.