Graphene-Fe_3O_4 nanocomposite(G-Fe_3O_4) was synthesized by a chemical co-precipitation method which was used as an efficient catalyst for the reduction of nitroarenes with hydrazine hydrate.The method has been applied to a broad range of compounds with different properties and the yields were in the range of 75%-92%.The G-Fe_3O_4 catalyst can be readily recovered and reused 5 times without significant loss of the catalytic activity. Graphene-Fe_3O_4 nanocomposite (G-Fe_3O_4) was synthesized by a chemical co-precipitation method which was used as an efficient catalyst for the reduction of nitroarenes with hydrazine hydrate. The method has been applied to a broad range of compounds with different properties and the yields were in the range of 75% -92%. The G-Fe_3O_4 catalyst can be readily recovered and reused 5 times without significant loss of the catalytic activity.