A catalyst‐ and oxidant‐free, highly efficient, scalable, and sustainable synthetic method is developed for the selenylative annulation of 2‐alkynyl biaryls or 2‐heteroaryl‐substituted alkynyl benzenes with readily available diselenides under electrochemical conditions to synthesize a wide variety of selanyl polycyclic aromatic hydrocarbons and polycyclic heteroaromatics in high to excellent yield up to 99% at room temperature in a short time (2‐5 h). The transformation required only electricity as a green reagent and produces hydrogen gas as the only innocuous byproduct. Notably, the green chemistry metrics of the protocol are found excellent. Mechanistic studies revealed a radical pathway being initiated by the