An efficient method for the synthesis of GO-chitosan bionanocomposite is demonstrated. Also, GO-chitosan is used as a green nanocatalyst in the synthesis of tetra-substituted imidazoles. This protocol has many advantages such as short reaction time, high yield, easy isolation of the catalyst and solvent-free conditions. We put upon Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyzes for the confirmation of the nanocomposite production.