The　main　function　of　Internet　of　Things　is　to　collect　and　transmit　data.　At　present,　the　data　transmission　in　Internet　of　Things　lacks　effective　trust　attestation　mechanism　and　trust　traceability　mechanism　of　data　source.　To　solve　the　above　problems,　a　trust　attestation　mechanism　for　sensing　layer　nodes　is　presented.　First　a　trusted　group　is　established,　and　the　node　which　is　going　to　join　the　group　needs　to　attest　its　identity　and　key　attributes　to　the　higher　level　node.　Then　the　dynamic　trust　measurement　value　of　the　node　can　be　obtained　by　measuring　the　node　data　transmission　behavior.　Finally　the　node　encapsulates　the　key　attributes　and　trust　measurement　value　to　use　short　message　group　signature　to　attest　its　trust　to　the　challenger.　This　mechanism　can　measure　the　data　sending　and　receiving　behaviors　of　sensing　nodes　and　track　the　data　source,　and　it　does　not　expose　the　privacy　information　of　nodes　and　the　sensing　nodes　can　be　traced　effectively.　The　trust　measurement　for　sensing　nodes　and　verification　is　applicable　to　Internet　of　Things　and　the　simulation　experiment　shows　the　trust　attestation　mechanism　is　flexible,　practical　and　efficient.　Besides,　it　can　accurately　and　quickly　identify　the　malicious　nodes　at　the　same　time.　The　impact　on　the　system　performance　is　negligible.　©　2017,　Wuhan　University　and　Springer-Verlag　GmbH　Germany.