The　revised　Szeged　index　of　a　graph　is　defined　as　Sz*　(G)　=Sigma(e=uv　is　an　element　of　E)(n(u)(e)　+　n(0)(e)/2　(n(v)(e)　+　n(0)(e)/2)　where　n(u)(e)　and　n(v)(e)　are,　respectively,　the　number　of　vertices　of　G　lying　closer　to　vertex　u　than　to　vertex　v　and　the　number　of　vertices　of　G　lying　closer　to　vertex　v　than　to　vertex　u,　and　n(0)(e)　is　the　number　of　vertices　equidistant　to　u　and　v.　In　the　paper,　we　acquired　the　lower　bound　of　revised　Szeged　index　among　all　tricyclic　graphs,　and　the　extremal　graphs　that　attain　the　lower　bound　are　determined.