A silanylamine-based compound is represented by Formula 1 below. An organic light-emitting device includes an organic layer that includes the silanylamine-based compound: wherein R1, R2, R3, R4, R5, R6, R7, R8, Ar1, Ar2, and Ar3 are as defined in the specification. The silanylamine-based compound has good electrical characteristics and charge transport capability, and thus, is useful as a hole injection material, a hole transport material, and/or an emitting material for fluorescent or phosphorescent devices capable of producing light of a full spectrum of colors, including red, green, blue, and white. Thus, the organic light-emitting device including the organic layer including the silanylamine-based compound shows high efficiency, a low driving voltage, and high brightness.