The invention discloses a method for detecting staphylococcus aureus based on reduced graphene oxide-nanogold composite material in combination with aptamer, belonging to the field of electrochemistry. According to the basic principle of the method, the reduced graphene oxide-nanogold composite material is used to modify a sulfhydrylation whole staphylococcus aureus capture probe by a layer by layer self-assembly method. When the probe is incubated in staphylococcus aureus liquid, effective binding sites of the probe can be bound with the staphylococcus aureus to wrap the staphylococcus aureus in a three-dimensional space structure, thus, the whole capture to target bacteria is realizes. The electron transmission on the surface of an electrode is blocked after the target bacteria is bound, so that a electrochemical resistance value increases, and quantitative determination on the staphylococcus aureus can be realized based on the change of the resistance value. By virtue of excellent electron transmission capability of graphene and large specific surface area of nanogold, detection signals can be amplified, and detection time can be shortened. The new method provided by the invention can be applied to whole bacteria detection on the staphylococcus aureus, can expand application of impedance-based electrochemical unmarked detection, and has the advantages of strong specificity, high sensitivity, cheapness, rapidness, and so on.