Localized surface plasmon resonance (LSPR) sensors have good potential for label-free non-invasive detection of biomolecules, healthcare diagnosis, disease monitoring, gas sensing, and food safety. For detection of low concentration small-sized bioanalytes (e.g., viruses, proteins, etc) the plasmonic field needs to be localized on a larger device surface area. Our study focuses on the optimization and fabrication of leaky Au nanoresonators based sensing platform for SARS-CoV-2 detection with uniform sensitivity over a 100 m 100 m active sensing area. The Au nanoresonator array was optimized to detect 100 nm sized bioanalytes as it matches the size of SARS-CoV-2. The performance of the optimized design was tested with 100 nm sized polystyrene beads which demonstrated a sensitivity of 17.05 ± 3.25 nm/decade. The Au nanoresonators were functionalized with anti-SARS-CoV-2 antibody to detect SARS-CoV-2. Our experimental results demonstrate the best detection sensitivity of 1.32 ± 0.08 nm/decade and limit of detection of 1 VLP L.