Organic electroluminescence device and polycyclic compound for organic electroluminescence device

An organic electroluminescence device comprising:

• a first electrode;
• an organic layer on the first electrode;
• and
• a second electrode on the organic layer,
• wherein the organic layer comprises a polycyclic compound represented by Formula 1 below:
• wherein, in Formula 1,
• X1 and X2 are each independently a substituted or unsubstituted amine group, an aryl group having 6 to 30 ring-forming carbon atoms and having at least one amine group as a substituent, or a substituted or unsubstituted heteroaryl group including at least one N having 2 to 30 ring-forming carbon atoms,
• R1 to R4 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted amine group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and
• a to d are each independently an integer of 0 to 4.