An organic electroluminescence device comprising: a first electrode; a hole transport region on the first electrode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a second electrode on the electron transport region, wherein the first electrode and the second electrode each independently include at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, In, Sn, and Zn, or a compound of two or more selected from them, a mixture of two or more selected from them, or oxides of one or more selected from them, wherein the emission layer comprises a fused polycyclic compound represented by the following Formula 1: in Formula 1, X 1 and X 2 are each independently BArs, O, S, or NAr 6, Ar 1 to Ar 6 are each independently a substituted or unsubstituted C 6 - C 60 aryl group, or a substituted or unsubstituted C 2 - C 60 heteroaryl group, Ar 1 and Ar 2 may be combined with each other to form a ring, R 1 to R 3 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amine group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted C 1 - C 20 alkyl group, a substituted or unsubstituted C 6 - C 60 aryl group, or a substituted or unsubstituted C 2 - C 60 heteroaryl group, and any of R 1 to R 3 are optionally combined with an adjacent group to form a ring, n 1 and n 2 are each independently an integer of 0 to 2, and n 3 and n 4 are each independently an integer of 0 to 4; characterized in that R 4 is a hydrogen atom, a halogen atom, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group. a first electrode; a hole transport region on the first electrode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a second electrode on the electron transport region, wherein the first electrode and the second electrode each independently include at least one selected from Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF / Ca, LiF / Al, Mo, Ti, In, Sn, and Zn, or a compound of two or more selected from them, a mixture of two or more selected from them, or oxides of one or more selected from them, wherein the emission layer comprises a fused polycyclic compound represented by the following Formula 1: in Formula 1, X 1 and X 2 are each independently BArs, O, S, or NAr 6, Ar 1 to Ar 6 are each independently a substituted or unsubstituted C 6 - C 60 aryl group, or a substituted or unsubstituted C 2 - C 60 heteroaryl group, Ar 1 and Ar 2 may be combined with each other to form a ring, R 1 to R 3 are each independently a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted amine group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted C 1 - C 20 alkyl group, a substituted or unsubstituted C 6 - C 60 aryl group, or a substituted or unsubstituted C 2 - C 60 heteroaryl group, and any of R 1 to R 3 are optionally combined with an adjacent group to form a ring, n 1 and n 2 are each independently an integer of 0 to 2, and n 3 and n 4 are each independently an integer of 0 to 4; characterized in that R 4 is a hydrogen atom, a halogen atom, a substituted or unsubstituted methyl group, or a substituted or unsubstituted phenyl group.