An emitting compound represented by Formula 2-1 or 2-3: wherein, in Formula 2-1 and 2-3, X is selected from the group consisting of B, P=O and P=S, Y 1 is selected from the group consisting of NR 1 , C(R 2 ) 2 , O, S, Se and Si(R 3 ) 2 , and Y 2 is O or S, each of R 1 to R 6 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, wherein in Formula 2-1, each of R 7 , R 8 , and R 9 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and wherein in Formula 2-3, each of Z 1 to Z 4 is independently N or CR 10 , and at least one of Z 1 to Z 4 is N, and each of R 7 to R 10 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl. Y 1 is selected from the group consisting of NR 1 , C(R 2 ) 2 , O, S, Se and Si(R 3 ) 2 , and Y 2 is O or S, each of R 1 to R 6 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, wherein in Formula 2-1, each of R 7 , R 8 , and R 9 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and wherein in Formula 2-3, each of Z 1 to Z 4 is independently N or CR 10 , and at least one of Z 1 to Z 4 is N, and each of R 7 to R 10 is independently selected from the group consisting of hydrogen, deuterium, C1 to C10 alkyl group unsubstituted or substituted with deuterium, C6 to C30 arylamine group unsubstituted or substituted with deuterium or C1 to C10 alkyl, C6 to C30 aryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl, and C5 to C30 heteroaryl group unsubstituted or substituted with deuterium or C1 to C10 alkyl. <EOS>