A　simple　one-pot　method　is　developed　to　prepare　positively　charged　aggregated　silver　nanoparticles　(a-AgNPs).　The　obtained　a-AgNPs　show　strong　localized　surface　plasmon　resonance　(LSPR)　absorption,　whose　wavelength　can　be　easily　tuned　to　match　the　commonly　used　lasers　in　surface　enhanced　Raman　scattering　(SERS).　Furthermore,　the　obtained　a-AgNPs　can　be　easily　fabricated　into　paper-based　SERS　chips　by　filtering　against　a　negatively　charged　filter　membrane.　On　the　basis,　a　convenient　SERS　sensor　has　been　developed　for　the　detection　of　thiram　using　a　785　nm　handheld　Raman　spectrometer.