A disinfecting composition comprising a quaternary ammonium acid compound and hydrogen peroxide is disclosed. An embodiment of the composition comprises a quaternary ammonium acid compound in a hydrogen peroxide/water solution. In addition, the composition can further comprise an acid. In addition, the composition does not comprise a cationic polymer. The disclosure also provides methods of using the same to kill or inhibit the growth of microorganisms, such as bacteria, viruses, fungi, mildew, and mold. The disclosure also provides for methods of disinfecting a substrate, preferably a hard surface, comprising applying a disinfecting composition of the invention to the substrate.