Gold nanoparticles (GNPs) have been extensively used in cancer research due to their abilities as anti-cancer drug carriers for chemotherapy and as dose enhancers in radiotherapy. Although most GNP research in the past involved cytoplasm localized GNPs, it is predicted that therapy response can be enhanced if GNPs can be effectively targeted into the nucleus. A strategy for designing a GNP-peptide complex for targeting the nucleus will be presented. Three different sequences of peptides (CKKKKKKGGAGDMFG, CGGRKKRRGRRRAP, CALNN) were conjugated onto GNPs. The first peptide was used to stabilize the complex, the second peptide to enhance uptake into the cell, while the third peptide was used to induce nuclear delivery. With nuclear targeting, more damage can be caused to the DNP of cancer cells upon irradiation. This research will establish a more successful NP-based platform that combines treatment modalities and more effectively approach cancer treatment.