In　this　work,　a　novel　＇turn-on＇　mode　Au　nanocubes　(AuNCs)　enhanced　surface-enhanced　Raman　scattering　(SERS)　biosensing　platform　coupled　with　heated　Au　electrode　(HAuE)　and　strand　displacement　amplification　(SDA)　strategy　was　proposed　for　highly　sensitive　detection　of　DNA　adenine　methylation　(Dam)　Methyltransferase　(MTase)　activity.　The　Dam　MTase　and　DpnI　enzyme　activities　were　significantly　increased　by　elevating　the　HAuE　surface　temperature,　resulting　in　the　rapid　production　of　template　DNA　for　later　SDA.　During　the　SDA　process,　the　released　single-stranded　DNA　(ssDNA)　could　be　amplified　exponentially,　and　its　concentration　was　positively　related　to　the　Dam　MTase　activity.　The　plasmonic　AuNCs　in　SERS　tags　could　provide　significant　SERS　enhancement　due　to　their　＇lightning　rod＇　effect　resulting　from　the　sharp　feature　of　the　edges　and　corners　of　AuNCs.　Because　of　these　factors,　the　proposed　biosensors　exhibited　high　sensitivity　in　detecting　the　Dam　MTase　activity.　The　limit　of　detection　was　estimated　to　be　8.65　×　10−5　U　mL−1,　which　was　lower　than　that　in　most　of　the　sensors　for　detection　of　Dam　MTase　activity　in　the　literature.　This　SERS　biosensor　could　also　be　used　to　screen　inhibitors　of　Dam　MTase　and　had　the　potential　for　detecting　Dam　MTase　activity　in　real　biological　samples.　©　2022　Elsevier　B.V.