Embodiments of the present disclosure provide a method for beam management in an unlicensed band, a terminal device, and a network device. The method includes: receiving, by a terminal device, a reference signal resource from a network device; measuring, by the terminal device, the reference signal resource in the unlicensed band, to obtain a beam measurement result; and sending, by the terminal device using an uplink resource for transmitting a beam report, the beam report comprising the beam measurement result.