A novel compound of Chemical Formula 1 and an organic light emitting device including the same:




where Y is O or S: Ar1 and Ar2 are each independently a substituted or unsubstituted C6-60 aryl or C2-60 heteroaryl containing one or more heteroatoms of N, O and S; A and B are each independently a C6-60 aromatic ring or a C2-60 heteroaromatic ring containing one or more heteroatoms of N, O and S which is fused with an adjacent pentagonal ring; D is deuterium; R1 and R2 are each independently deuterium or a substituted or unsubstituted C6-60 aryl or C2-60 heteroaryl containing one or more heteroatoms of N, O and S, provided that at least one of R1 and R2 is deuterium; and the other substituent are as defined in the specification.