An organic electroluminescent device comprising one or more light emitting layers between an anode and a cathode opposite to each other, wherein at least one of the light emitting layers contains an organic emission material having a difference between excited singlet energy (S1) and excited triplet energy (T1) (ΔEST) of 0.20 eV or less as a light emitting dopant, a first host selected from the compounds represented by the following general formula , and a second host selected from the compounds represented by the following general formula : wherein X 1 represents O, S, or N-Ar 1 ; Ar 1 independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof; R 1 independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms; a and d represent an integer of 0 to 4; and b and c represent an integer of 0 to 3, wherein X 2 independently represents N or C-H, and at least two X 2 represent N; Ar 2 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof; R 2 independently represents deuterium, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms; and e, f, g, and h represent an integer of 0 to 4; characterized in that the organic emission material is a boron-containing polycyclic aromatic compound represented by the following general formula or : wherein X 3 represents N-Ar 3 , O, or S, and at least one X 3 represents N-Ar 3 ; Ar 3 independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof; R 3 independently represents a cyano group, deuterium, a diarylamino group having 12 to 44 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms; i and j represent an integer of 0 to 4; and k represents an integer of 0 to 3, wherein X 4 represents N-Ar 4 , O, or S, and at least one X 4 represents N-Ar 4 ; Ar 4 independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking 2 to 8 aromatic rings thereof; R 4 independently represents a cyano group, deuterium, a diarylamino group having 12 to 44 carbon atoms, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted aromatic heterocyclic group having 3 to 17 carbon atoms; m and n represent an integer of 0 to 4; o and p represent an integer of 0 to 3; and q represents an integer of 0 to 2. <EOS>