A user terminal according to a first feature is used in a mobile communication system. The use terminal includes: a receiver configured to receive a measurement instruction to instruct measurement in an unlicensed band, from a base station; a controller configured to, in response to reception of the measurement instruction, search for a radio signal transmitted in a frequency channel included in the unlicensed band, and measure reception power of the radio signal detected by the search, even when a cell identifier of a measurement target cell is not designated in the measurement instruction; and a transmitter configured to transmit a measurement report including an identifier of a transmission source of the detected radio signal and a measurement result of the reception power, to the base station.