Herein, a method for the assembly of biologically valuable 3‐selenospiro[4,5]decatrienones through CuBr2‐catalyzed ispo‐cyclization of Se powder, boronic acids, and N‐(p‐methoxyaryl)propiolamides has been established. In this protocol, noble transition metal, prefunctionalized selenylation reagent, and strong chemical oxidant are not employed. This method feature wide substrate scope, good functional group tolerance, easy operation, and employing earth‐abundant metal as catalyst and green air as oxidant. Furthermore, several derivatizations of 3‐selenospiro[4,5]decatrienones are performed to showcase the practicability of our strategy.