Graphene oxide (GO) was synthesized and functionalized with (3-chloropropyl)-trimethoxysilane (CPTMS) and then with 1,1,3,3-tetramethylguanidine (TMG) to produce GO-Si-TMG. The resultant material was characterized by elemental analysis, FT-IR, TGA and FE-SEM spectroscopy and was used in Michael addition of different C-nucleophiles to various substituted nitrostyrenes to explore its catalytic activity. GO-Si-TMG showed very good catalytic activity and gave a conversion of >99.99 % (based on 1H NMR of the crude reaction mixture) under the optimized reaction conditions (r.t., EtOH-H2O (1:1), 1.5 h). Moreover, it could be easily recovered through filtration and reused for at least seven times without significant decrease in its catalytic performance.