The nanotechnology has recently gained the attention and vast area for research. The biologically synthesis of nanoparticles are eco-friendly, cost effective and non toxic nature. The present study on the reduction of Selenium ions to Selenium nanoparticles mediated through Aloe vera leaf extract were demonstrated with an experimental procedure. The synthesized nanoparticles were characterized using UV-Visible spectrophotometer, Transmission electron microscopy (TEM), Fourier transform spectroscopy (FT-IR) and Energy dispersive X-Ray spectroscopy (EDAX). The selenium nanoparticles synthesized by Aloe vera leaf extract observed as hollow and spherical particles in size ranging 9-58 nm which found more stable more than two months.