Background:　Pathogenic　bacteria　have　always　been　a　significant　threat　to　human　health.　The　detection　of　pathogens　needs　to　be　rapid,　accurate,　and　convenient.　Methods:　We　present　a　sensitive　surface-enhanced　Raman　scattering　(SERS)　biosensor　based　on　the　combination　of　vancomycin-modified　Ag-coated　magnetic　nanoparticles　(Fe3O4@Ag-Van　MNPs)　and　Au@Ag　nanoparticles　(NPs)　that　can　effectively　capture　and　discriminate　bacterial　pathogens　from　solution.　The　high-performance　Fe3O4@Ag　MNPs　were　modified　with　vancomycin　and　used　as　bacteria　capturer　for　magnetic　separation　and　enrichment.　The　modified　MNPS　were　found　to　exhibit　strong　affinity　with　a　broad　range　of　Gram-positive　and　Gram-negative　bacteria.　After　separating　and　rinsing　bacteria,　Fe3O4@Ag-Van　MNPs　and　Au@Ag　NPs　were　synergistically　used　to　construct　a　very　large　number　of　hot　spots　on　bacteria　cells,　leading　to　ultrasensitive　SERS　detection.　Results:　The　dominant　merits　of　our　dual　enhanced　strategy　included　high　bacterial-capture　efficiency　(＞　65%)　within　a　wide　pH　range　(pH　3.0-11.0),　a　short　assay　time　(＜　30min),　and　a　low　detection　limit　(5x10(2)　cells/mL).　Moreover,　the　spiked　tests　show　that　this　method　is　still　valid　in　milk　and　blood　samples.　Owing　to　these　capabilities,　the　combined　system　enabled　the　sensitive　and　specific　discrimination　of　different　pathogens　in　complex　solution,　as　verified　by　its　detection　of　Gram-positive　bacterium　Escherichia　coli,　Gram-positive　bacterium　Staphylococcus　aureus,　and　methicillin-resistant　S.　aureus.　Conclusion:　This　method　has　great　potential　for　field　applications　in　food　safety,　environmental　monitoring,　and　infectious　disease　diagnosis.