Hemicellulose was separated from bamboo using alkaline method. Silver nanomaterials had been prepared using the hemicellulose as template and silver nitrate as precursor via a green approach. The synthesized samples were characterized by UV-vis, XRD, and SEM techniques. UV-visible spectrum and XRD diffraction pattern revealed that the silver ion (Ag+) had been reduced to the metallic silver nanoparticles (Ag0). The results demonstrated that after calcination at 500 °C in air atmosphere, nano Ag/C compound was obtained. The hemicellulose acted as an effective nanoreactor for the in situ synthesis of silver nanoparticles. This novel procedure provides a facile and environmental way to manufacture silver nanoparticles for various applications.