Molybdenum(V)-mediated cleavage of C(sp2)-Se bond and C(sp2)-H bond as well as intramolecular oxidative C(sp2)-Se coupling reaction of phenylselenyl-functionalized arenes or heterocycles has been developed. Three kinds of benzoselenophene frameworks were constructed through this reaction with yields up to 94%. This new C(sp2)-Se bond-switching methodology may provide a new strategy for interesting applications of phenylselenyl-substituted aromatic compounds in the synthesis of selenium-containing heterocycles and natural products.