Optical whispering-gallery-mode (WGM) cavities have gained appreciable curiosity due to their distinctive properties of light-matter interactions enhancement. Standard WGM sensing is predicated on the mechanisms of mode shift, mode broadening, or mode splitting, which requires a small mode quantity and an ultrahigh Q-factor. In addition to, the WGM sensing suffers from an absence of the specificity in figuring out substance, and extra chemical functionalization or the incorporation of plasmonic supplies are required for good specificity. Herein, we suggest a brand new sensing methodology primarily based on a person WGM cavity to realize ultrasensitive and high-specificity molecular sensing, which mixes the options of enhanced light-matter interactions on WGM cavity and the “fingerprint spectrum” of surface-enhanced Raman scattering (SERS). This methodology identifies the substance by monitoring the Raman sign enhanced by WGM cavity relatively than monitoring the variation of WGM itself. Subsequently, ultrasensitive and high-specificity molecular sensing might be completed even on a low-Q cavity. The working rules of the proposed sensing methodology had been additionally systematically investigated by way of photoinduced cost switch, Purcell impact, and optical resonance coupling. This work gives a brand new WGM sensing strategy in addition to a method within the design of high-performance SERS substrate by creating optical resonance mode.