An organic compound represented by Chemical Formula A or Chemical Formula B: wherein, X1 is CR11 or N, X2 is CR12 or N, X3 is CR13 or N, X4 is CR14 or N, X5 is CR15 or N, X6 is CR16 or N, X7 is CR17 or N, X8 is CR18 or N, X9 is CR19 or N, and X10 is CR20 or N, wherein at least two of X1 to X4 are selected from among CR11 to CR14 and at least three of X5 to X10 are selected from among CR15 to CR20, with a proviso that one of X1 to X10 is a carbon atom connected to A1 the substituents R1, R2, and R11 to R20, which may be the same or different, are each independently selected from among a hydrogen, a deuterium, a substituted or unsubstituted alkyl of 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl of 3 to 30 carbon atoms, a substituted or unsubstituted aryl of 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl of 2 to 50 carbon atoms bearing O, N, or S as a heteroatom, an alkylsilyl of 1 to 24 carbon atoms, an arylsilyl of 6 to 24 carbon atoms, a nitro and a halogen, L1 denotes a linker and is any one selected from among a single bond, a substituted or unsubstituted arylene of 6 to 60 carbon atoms, and a substituted or unsubstituted heteroarylene of 2 to 60 carbon atoms, n is an integer of 0 to 3, with a proviso that when n is 2 or greater, the corresponding L1 linkers may be the same or different, and Ar1 and Ar2, which may be the same or different, are each independently any one selected from among a substituted or unsubstituted aryl of 6 to 40 carbon atoms and a substituted or unsubstituted heteroaryl of 2 to 30 carbon atoms, with a proviso that Ar1 may be connected to L1 to form a fused ring and Ar2 may be connected to L1 to form a fused ring in A1, wherein the organic compound represented by Chemical Formula A or Chemical Formula B has A1 bonded to position 1 of the dibenzofuran moiety thereof in such a manner that A1 is bonded to the carbon atom of X6 in Chemical Formula A and X7 in Chemical Formula B, wherein the term 'substituted' in the expression 'substituted or unsubstituted' means having at least one substituent selected from the group consisting of a deuterium, a cyano, a halogen, a nitro, an alkyl of 1 to 24 carbon atoms, a halogenated alkyl of 1 to 24 carbon atoms, an aryl of 6 to 24 carbon atoms, an arylalkyl of 6 to 24 carbon atoms, a heteroaryl of 2 to 24 carbon atoms or a heteroarylalkyl of 2 to 24 carbon atoms, an alkylsilyl of 1 to 24 carbon atoms and an arylsilyl of 1 to 24 carbon atoms, wherein compounds 301, 302, 304, 305, 307, 317, 319 and 320 are excluded: X1 is CR11 or N, X2 is CR12 or N, X3 is CR13 or N, X4 is CR14 or N, X5 is CR15 or N, X6 is CR16 or N, X7 is CR17 or N, X8 is CR18 or N, X9 is CR19 or N, and X10 is CR20 or N, wherein at least two of X1 to X4 are selected from among CR11 to CR14 and at least three of X5 to X10 are selected from among CR15 to CR20, with a proviso that one of X1 to X10 is a carbon atom connected to A1 the substituents R1, R2, and R11 to R20, which may be the same or different, are each independently selected from among a hydrogen, a deuterium, a substituted or unsubstituted alkyl of 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl of 3 to 30 carbon atoms, a substituted or unsubstituted aryl of 6 to 50 carbon atoms, a substituted or unsubstituted heteroaryl of 2 to 50 carbon atoms bearing O, N, or S as a heteroatom, an alkylsilyl of 1 to 24 carbon atoms, an arylsilyl of 6 to 24 carbon atoms, a nitro and a halogen, L1 denotes a linker and is any one selected from among a single bond, a substituted or unsubstituted arylene of 6 to 60 carbon atoms, and a substituted or unsubstituted heteroarylene of 2 to 60 carbon atoms, n is an integer of 0 to 3, with a proviso that when n is 2 or greater, the corresponding L1 linkers may be the same or different, and Ar1 and Ar2, which may be the same or different, are each independently any one selected from among a substituted or unsubstituted aryl of 6 to 40 carbon atoms and a substituted or unsubstituted heteroaryl of 2 to 30 carbon atoms, with a proviso that Ar1 may be connected to L1 to form a fused ring and Ar2 may be connected to L1 to form a fused ring in A1, wherein the organic compound represented by Chemical Formula A or Chemical Formula B has A1 bonded to position 1 of the dibenzofuran moiety thereof in such a manner that A1 is bonded to the carbon atom of X6 in Chemical Formula A and X7 in Chemical Formula B, wherein the term 'substituted' in the expression 'substituted or unsubstituted' means having at least one substituent selected from the group consisting of a deuterium, a cyano, a halogen, a nitro, an alkyl of 1 to 24 carbon atoms, a halogenated alkyl of 1 to 24 carbon atoms, an aryl of 6 to 24 carbon atoms, an arylalkyl of 6 to 24 carbon atoms, a heteroaryl of 2 to 24 carbon atoms or a heteroarylalkyl of 2 to 24 carbon atoms, an alkylsilyl of 1 to 24 carbon atoms and an arylsilyl of 1 to 24 carbon atoms, wherein compounds 301, 302, 304, 305, 307, 317, 319 and 320 are excluded: