An organic light-emitting medium including a pyrene derivative represented by the following formula (1) and a phenyl-substituted anthracene derivative represented by the following formula (2): n n n n n n n n n n wherein Ar 1 to Ar 4 are independently a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms.