Multi-agent　technologies　have　been　widely　applied　to　many　applications,　such　as　in　e-markets,　cloud　computing,　service-oriented　environments,　etc.　In　real　applications,　service-oriented　environments　are　open　and　dynamic,　where　loosely　coupled　agents　interact　to　consume　and　provide　services.　How　to　accurately　evaluate　the　potential　performance　(i.e.,　QoS)　of　service　providers　on　the　service　requested　by　a　service　consumer　in　such　open　and　dynamic　environments　is　a　challenging　issue　in　both　theory　and　practice.　In　this　paper,　an　innovative　approach　is　proposed　to　evaluate　the　QoS　of　service　providers　in　service-oriented　environments.　The　proposed　approach　first　borrows　the　reference　report　mechanism　from　the　certified　reputation　model,　so　as　to　efficiently　collect　reference　reports　(i.e.,　historical　performance)　of　service　providers　in　open　and　dynamic　environments.　Then,　a　tensor-based　QoS　model　is　proposed　to　construct　multi-dimensional　relationships　between　QoS　evaluation　factors　and　the　QoS　values　of　service　providers　based　on　the　collected　reference　reports.　The　QoS　evaluation　factors　include　the　type　of　services,　the　performance　of　service　providers,　the　subjectivity　of　service　consumers,　the　time　slot　of　reference　reports.　Finally,　a　CANDECOMP/PARAFAC　decomposition　and　gradient　descent-based　mechanism　is　used　to　evaluate　the　QoS　values　of　service　providers　through　completing　the　missing　entry　values　in　the　constructed　tensor.　The　uniform　random　simulation　experiments　indicate　that　the　proposed　approach　can　achieve　efficient　and　accurate　QoS　evaluation　in　service-oriented　environments　with　only　limited　collected　reference　reports,　especially　when　some　service　providers　do　not　have　reference　reports.