The present invention provides an OLED in which an organic thin film emissive layer comprising a single layer or plural layers between a cathode and an anode, wherein the organic thin film layer comprises at least one organic light emitting layer, wherein at least one light emitting layer comprises at least one host material and at least one phosphorescent emitter material, wherein the host material comprises a substituted or unsubstituted hydrocarbon compound having the chemical structure represented by the following formula: wherein at least one of Ar 1 to Ar 3 is represented by the following formula: wherein at least X 1 to X 3 are independently a nitrogen atom or CR 2 , provided that two of X 1 to X 3 are a nitrogen atom, R 1 is a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 ring carbon atoms, a substituted or unsubstituted silyl group, an aryl group having 6 to 50 ring carbon atoms, a heteroaryl group having 5 to 50 ring atoms, a halogen atom or a cyano group, R 2 is a hydrogen atom or a group represented by R 1 , a is an integer of 1 to 2 and n is an integer of 0 to 3, L 1 is a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, L 2 is a substituted or unsubstituted arylene group having 6 to 50 ring carbon atoms, or a substituted or unsubstituted heteroarylene group having 5 to 50 ring atoms, at most two of Ar 1 to Ar 3 that are not the group of formula (2) are independently a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, when L 1 , L 2 and/or at most two of Ar 1 to Ar 3 that are not the group of formula (2) are a substituted group, the substitutes are independently a linear or branched alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 ring carbon atoms, a substituted or unsubstituted silyl group, an aryl group having 6 to 14 ring carbon atoms, a heteroaryl group having 5 to 20 ring atoms, a halogen atom or a cyano group, when two or more of Ar 1 to Ar 3 are the groups of formula (2), the groups of formula (2) may be the same or different, when a is 2, R 1 S may be the same or different, and when n is 2 or more, L 2 S may be the same or different; and the phosphorescent emitter material comprises a phosphorescent organometallic complex having a substituted chemical structure represented by one of the following partial chemical structures represented by the following formulas: wherein each R is independently selected from the group consisting of H, alkyl, alkenyl, alkynyl, CN, CF 3 , C n F 2n+1 , trifluorovinyl, CO 2 R, C(O)R, NR 2 , NO 2 , OR, halo, aryl, heteroaryl, substituted heteroaryl or a heterocyclic group.