The　dynamic　viscosities　of　n-dodecane　were　measured　at　temperatures　between　303.3　and　693.3　K　and　pressures　up　to　10.0　MPa　using　a　dual-capillary　viscometer.　The　accuracy　of　the　dual-capillary　viscometer　was　improved　by　considering　centrifugal　effects　and　the　thermal　expansion　of　the　capillary.　The　combined　relative　standard　uncertainty　in　the　dynamic　viscosity　was　calculated　to　be　0.58-2.92　%.　This　study　provides　new　data　to　check　the　accuracy　of　Huber＇s　correlations　at　supercritical　pressures,　and　a　small　proportion　of　the　data　points　at　supercritical　conditions　where　few　experimental　data　have　been　reported.　The　average　absolute　deviation　between　the　experimental　data　and　the　calculated　data　from　Huber＇s　correlations　is　0.97%,　and　the　maximum　absolute　deviation　is　6.79%.　In　the　near-critical　and　supercritical　region,　the　accuracy　of　viscosities　of　n-dodecane　needs　more　experimental　data　for　verification　and　to　extend　the　theories.