Nano-petri-dish array assisted glancing angle Ag-sputtering was reported to synthesize Ag-nanoparticle (Ag-NP) assembled bi-nanoring arrays as surface-enhanced Raman scattering (SERS) substrates. By manipulating the sputtering-Ag duration, the gaps between the Ag-NPs in the bi-nanorings are tunable to acquire optimal electromagnetic field enhancement, and the ordered bi-nanoring arrays ensure excellent reproducibility for Raman measurement. Such as-fabricated Ag-NPs assembled nanoring arrays exhibit excellent SERS performance, not only 1 × 10(-12) M rhodamine 6G has been identified, but also polychlorinated biphenyls with a low concentration down to 1 × 10(-9) M has been recognized, showing great potential in the detection of trace organic pollutants in the environment.