Disclosed is an ultrasonic osteotome bit, which comprises a bit bar (1), a bit tip (2), and a liquid injection portion (3), one end of the liquid injection portion (3) being connected to the bit bar (1) and the other end of the liquid injection portion (3) being connected to the bit tip (2), wherein the ultrasonic osteotome bit further comprises a hollow liquid injection channel (10), the hollow liquid injection channel (10) penetrates from a tail end of the bit bar (1) to the liquid injection portion (3) along an axial direction of the bit bar (1), the liquid injection portion (3) is provided with a transverse liquid guide channel (20) penetrating transversely, i.e. substantially perpendicular to an axis of the bit bar (1), the transverse liquid guide channel (20) is in communication with the hollow liquid injection channel (10), and the transverse liquid guide channel (20) forms openings in lateral faces of the liquid injection portion (3). The ultrasonic osteotome bit allows a cooling liquid to sufficiently flow to the bit without being excited or scattered by ultrasonic vibration, thereby ensuring that the bit tip (2) is sufficiently cooled during use.