Internet　of　things　has　been　widely　applied　to　industrial　control,　smart　city　and　environmental　protection,　in　these　application　scenarios,　sensing　node　needs　to　make　real-time　response　to　the　feedback　control　of　the　application　layer.　Therefore,　it　is　necessary　to　monitor　whether　or　not　awareness　nodes　are　trusted　in　real　time,　but　the　existing　mechanisms　for　trusted　certification　lack　the　real-time　measurement　and　tracking　of　the　sensing　node.　To　solve　the　above　problems,　this　paper　proposes　a　dynamic　metric　based　authentication　mechanism　for　sensing　nodes　of　Internet　of　things.　Firstly,　the　dynamic　trustworthiness　measure　of　the　sensing　nodes　is　carried　out　by　introducing　the　computational　function　such　as　the　trust　function,　the　trustworthiness　risk　assessment　function,　the　feedback　control　function　and　the　active　function　of　the　sensing　node.　The　dynamic　trustworthiness　measure　of　sensing　nodes　from　multiple　dimensions　can　effectively　describe　the　change　of　trusted　value　of　sensing　nodes.　Then,　on　the　basis　of　this,　a　trusted　attestation　based　on　node　trusted　measure　is　realized　by　using　the　revocable　group　signature　mechanism　of　local　verifier.　The　mechanism　has　anonymity,　unforgeability　and　traceability,　which　is　proved　the　security　in　the　standard　model.　Simulation　experiments　show　that　the　proposed　trusted　attestation　mechanism　is　flexible,　practical　and　efficient　and　has　better　attack　resistance.　It　can　effectively　guarantee　the　reliable　data　transmission　of　nodes　and　realize　the　dynamic　tracking　of　node　reliability,　which　has　a　lower　impact　on　system　performance.