This work reports a green method for the synthesis of aryl selenocyanates via a three‐component reaction of arylboronic acids, Se powder, and trimethylsilyl cyanide (TMSCN) under metal‐free and additive‐free conditions. Remarkably, TMSCN acts as not only the substrate, but also the catalyst. Various selenaheterocycles can be also accessed with a catalytic amount of TMSCN.