Abstract: The present invention discloses a non-labeled virus detection substrate, system, and method based on inverted multi-angular cavity arrays. The virus detection substrate is used together with a Raman spectrometer for virus detection. The virus detection substrate has a metal layer disposed thereon, and inverted multi-angular cavities are formed in the metal layer. The cavities are arranged in a microarray. In order to detect the target, the size of the cavities should be adjusted first. Then, a laser with an optimized wavelength is applied to induce the effect of the surface enhanced Raman scattering.