Abstract—Au nanoneedle arrays were fabricated using a focused ion beam (fibAu_NN). With rhodamine 6G used as the probe molecule on the optimized Surface-enhanced Raman scattering (SERS) substrate, an enhancement of 7 orders of magnitude was obtained at low concentration (10-5 M). Moreover, a strong electromagnetic field effect is generated in and around these NNs, creating localized surface plasmon resonance. In the biological assessment, the optimized fibAu_NN substrate was able to distinguish cancer and normal cells. The SERS effect was extensively increased at incident laser interacted area of cells and sharp NNs surfaces.