The present disclosure is designed to reduce the load of inter-frequency measurements in user terminals in a radio communication system in which a plurality of component carriers (CCs) are used in each small cell within a macro cell. The inter-frequency measurement method of the present disclosure includes the steps of, from a radio base station forming a macro cell to a user terminal, transmitting the transmission timing information of a detection signal in a small cell, and a timing shift value for detection signals of the plurality of CCs that transmitted with shifted timings in the small cell, and, in the user terminal, measuring the plurality of CCs in a measurement gap based on the transmission timing information and the timing shift value.