An organic thin film, comprising: a first compound represented by Chemical Formula 1A, and a second compound that is different from the first compound, the second compound represented by Chemical Formula 2A: wherein, in Chemical Formulae 1A and 2A, X 11, X 12, X 21, and X 22 are independently one of O, S, Se, Te, and NR a, Ar 1 and Ar 2 independently comprise at least one substituted or unsubstituted benzene, at least one substituted or unsubstituted furan ring, at least one substituted or unsubstituted thiophene ring, at least one substituted or unsubstituted selenophene ring, at least one substituted or unsubstituted tellurophene ring, or a fused ring of two or more of the foregoing rings, Ar 1 and Ar 2 of Chemical Formulae 1A and 2A independently include one to eight rings, R 11 and R 12 are different from each other or R 13 and R 14 are different from each other, R 21 and R 22 are different from each other or R 23 and R 24 are different from each other, R 11 to R 14, R 21 to R 24, and R a are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C3 to C30 cycloalkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C3 to C30 heterocycloalkyl group, a substituted or unsubstituted C3 to C30 heterocycloalkenyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 alkylaryl group, a substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C3 to C30 heteroaryl group, a substituted or unsubstituted C4 to C30 alkylheteroaryl group, a halogen, a cyano group, or a combination thereof, and n1 and n2 are independently 0 or 1. a first compound represented by Chemical Formula 1A, and a second compound that is different from the first compound, the second compound represented by Chemical Formula 2A: wherein, in Chemical Formulae 1A and 2A, X 11, X 12, X 21, and X 22 are independently one of O, S, Se, Te, and NR a, Ar 1 and Ar 2 independently comprise at least one substituted or unsubstituted benzene, at least one substituted or unsubstituted furan ring, at least one substituted or unsubstituted thiophene ring, at least one substituted or unsubstituted selenophene ring, at least one substituted or unsubstituted tellurophene ring, or a fused ring of two or more of the foregoing rings, Ar 1 and Ar 2 of Chemical Formulae 1A and 2A independently include one to eight rings, R 11 and R 12 are different from each other or R 13 and R 14 are different from each other, R 21 and R 22 are different from each other or R 23 and R 24 are different from each other, R 11 to R 14, R 21 to R 24, and R a are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C3 to C30 cycloalkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C3 to C30 heterocycloalkyl group, a substituted or unsubstituted C3 to C30 heterocycloalkenyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 alkylaryl group, a substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C3 to C30 heteroaryl group, a substituted or unsubstituted C4 to C30 alkylheteroaryl group, a halogen, a cyano group, or a combination thereof, and n1 and n2 are independently 0 or 1. X 11, X 12, X 21, and X 22 are independently one of O, S, Se, Te, and NR a, Ar 1 and Ar 2 independently comprise at least one substituted or unsubstituted benzene, at least one substituted or unsubstituted furan ring, at least one substituted or unsubstituted thiophene ring, at least one substituted or unsubstituted selenophene ring, at least one substituted or unsubstituted tellurophene ring, or a fused ring of two or more of the foregoing rings, Ar 1 and Ar 2 of Chemical Formulae 1A and 2A independently include one to eight rings, R 11 and R 12 are different from each other or R 13 and R 14 are different from each other, R 21 and R 22 are different from each other or R 23 and R 24 are different from each other, R 11 to R 14, R 21 to R 24, and R a are independently hydrogen, a substituted or unsubstituted C1 to C30 alkyl group, a substituted or unsubstituted C2 to C30 alkenyl group, a substituted or unsubstituted C2 to C30 alkynyl group, a substituted or unsubstituted C3 to C30 cycloalkyl group, a substituted or unsubstituted C3 to C30 cycloalkenyl group, a substituted or unsubstituted C1 to C30 alkoxy group, a substituted or unsubstituted C3 to C30 heterocycloalkyl group, a substituted or unsubstituted C3 to C30 heterocycloalkenyl group, a substituted or unsubstituted C6 to C30 aryl group, a substituted or unsubstituted C7 to C30 alkylaryl group, a substituted or unsubstituted C6 to C30 aryloxy group, a substituted or unsubstituted C3 to C30 heteroaryl group, a substituted or unsubstituted C4 to C30 alkylheteroaryl group, a halogen, a cyano group, or a combination thereof, and n1 and n2 are independently 0 or 1.