Rapid　and　quantitative　detection　of　bacterial　antibiotic　resistance　is　of　great　significance　for　the　prevention　and　treatment　of　infections　and　understanding　drug-resistant　mechanism.　In　this　study,　label-free　surface-enhanced　Raman　spectroscopy　(SERS)　technology　was　applied　to　dynamically　explore　oxacillin/cefazolin-derived　resistance　in　Staphylococcus　aureus　using　a　portable　Raman　spectrometer.　The　results　showed　that　S.　aureus　rapidly　responded　to　oxacillin/cefazolin　stimulation　and　gradually　developed　different　degrees　of　drug　resistance　during　the　21　days　of　exposure.　The　molecular　changes　that　accumulated　in　the　drug-resistant　strains　were　sensitively　recorded　by　SERS　in　a　whole-cell　manner.　Principal　components-linear　discriminant　analysis　correctly　distinguished　various　degrees　of　drug　resistant　strains.　The　typical　Raman　peak　intensities　of　I-734/I-867　showed　a　negative　and　non-linear　correlation　with　the　minimum　inhibitory　concentration　(MIC).　The　correlation　coefficient　reached　above　0.9.　The　target　sites　of　oxacillin/cefazolin　on　S.　aureus　clearly　reflected　on　SERS　profiles.　The　results　collected　by　SERS　were　further　verified　by　other　biological　methods　including　the　antibiotic　susceptibility　test,　MIC　determination,　and　PCR　results.　This　study　indicates　that　SERS　technology　provides　a　rapid　and　flexible　alternative　to　current　drug　susceptibility　testing,　laying　a　foundation　for　qualitative　and　quantitative　evaluation　of　drug　resistance　in　clinical　detection.　(C)　2022　Elsevier　B.V.　All　rights　reserved.