Organic-inorganic hybrid sol-gel coatings are an effective method to improve the corrosion resistance of magnesium and its alloys. Accordingly, in this work, tetraethylorthosilicate and methylthreeethoxy silane with good mechanical and chemical barrier properties were used to prepare the sol-gel coatings. Alanine, glutamine, and methionine were added as green inhibitors to the coatings. It was found that among the inhibitors studied, the most enhanced performance is related to 0.5 wt% of methionine with the total corrosion resistance of 47 k Omega cm(2). The effect of cloisite Na+, cloisite 20A, and cloisite 30B as nanoparticle additives was also investigated. The results indicated that cloisite Na+ with the composition of 0.5 wt% shows more enhanced performance than the others. Simultaneous presence of the optimum contents of methionine and cloisite Na+ in the coatings demonstrated their synergistic effect, where R-total became 434 k Omega cm(2). Barrier properties of the prepared coatings were examined by electrochemical impedance spectroscopy and their characterization was performed by scanning electron microscopy, atomic force microscopy, Fourier transform infrared, and X-ray diffraction techniques.