A simple method has been successfully developed to synthesize Pd@Au core/shell nanosheets for 3 h at room temperature. It indicates to be an eco-friendly and simple method for the synthesis of Pd@Au core/shell nanosheets. The thickness of Au shells covered on the Pd nanosheets’ surfaces were formed at room temperature in 3 hours. The prepared Pd@Au core/shell nanosheets have been characterized by UV-vis, XRD, TEM, HRTEM, elemental-mapping EDX and EDX line profile. The prepared Pd@Au core/shell nanosheets could be a promising material for applications in the field of sensing, biosensor, image, determination of biomolecules and biomarkers, photothermal therapy, and optical catalyst, etc. in the current time and in future.