Gold nanoparticles (size from 10 to 50 nm) were synthesized by three different methods and were characterized by UV-Vis spectroscopy and transmission electron microscopy (TEM). The shape and size distribution of gold nanoparticles were determined. The interaction of major storage protein extracted and purified from aleurone cells of barley with the gold colloids has been examined using absorption UV-Vis spectroscopy and TEM observations. These investigations evidence the binding of aleurone protein to gold nanoparticles. This binding might occur by electrostatic forces between the negatively charged citrate capped gold particles and the positively charged groups of the protein (e.g., arginine and lysine residues).