Organoselenium compounds and quinolines are widely used in drugs and materials. Herein, we report an electro-oxidative cyclization between isocyanides and diselenides to effectively synthesize 2-organoselenyl quinolines in a simple undivided cell without transition-metal catalysts or toxic oxidants. Gram-scale synthesis and postsynthetic modifications highlighted the practicality of this electrochemical strategy. A series of 2-organoselenyl quinolines are produced with up to 82% yield, good functional group tolerance and high atom efficiency under room temperature.