Embodiments of the present invention disclose a radio link monitoring method and UE. The radio link monitoring method provided in the embodiments of the present invention includes: monitoring, by user equipment UE, downlink quality of a serving cell on a physical layer by using an extended link monitoring period, where the extended link monitoring period is greater than an original link monitoring period; and sending, by the UE, an in-synchronization indication message or an out-of-synchronization indication message to an upper layer of the UE when a monitoring result satisfies a preset report condition. According to the method in the embodiments of the present invention, power consumption and device costs can be reduced.