A light emitting element of one or more embodiments includes a first electrode, a second electrode, and a polycyclic compound represented by Formula 1 below in an emission layer disposed between the first electrode and the second electrode, thereby showing high emission efficiency properties: The polycyclic compound is of a DABNA structure includes one heteroaryl group substituted at a para position to boron, and two bulky substituents substituted at meta positions to the boron.