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Among the transitional metal dichalcogenides (TMDCs), molybdenum disulfide (MoS₂) is considered an outstanding candidate for biosensing applications due to its high absorptivity and amenability to ionic current measurements. Dielectric metasurfaces have also emerged as a powerful platform for novel optical biosensing due to their low optical losses and strong near-field enhancements. Once functionalized with TMDCs, dielectric metasurfaces can also provide strong photon–exciton interactions. Here, we theoretically integrated a single layer of MoS₂ into a CMOS-compatible asymmetric dielectric metasurface composed of TiO₂ meta-atoms with a broken in-plane inversion symmetry on an SiO₂ substrate. We numerically show that the designed MoS₂-integrated metasurface can function as a high-figure-of-merit (<inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>FoM</mi><mo>=</mo><mn>137.5</mn><mo> </mo><msup><mrow><mi>RIU</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></semantics></math></inline-formula>) van der Waals-based biosensor due to the support of quasi-bound states in the continuum. Moreover, owing to the critical coupling of the magnetic dipole resonances of the metasurface and the A exciton of the single layer of MoS₂, one can achieve a <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>55</mn><mo>%</mo></mrow></semantics></math></inline-formula> enhanced excitonic absorption by this two-port system. Therefore, the proposed design can function as an effective biosensor and is also practical for enhanced excitonic absorption and emission applications.