The present invention is designed so that a fading frequency estimation method that can improve the mobility of user terminals in a HetNet can be provided. The fading frequency estimation method according to the present invention includes the steps, in which a radio base station arranges reference signals, using an arrangement format, in which the reference signals, which are used to estimate the fading frequency in the user terminal, are arranged in a relatively high density, in at least part of the radio resources allocated for a downlink shared data channel, and transmits allocation information of the radio resources for the downlink shared data channel to the user terminal, and the user terminal estimates the fading frequency based on the channel estimation values of the reference signals, and transmits the estimated fading frequency to the radio base station in response to a transmission request from the radio base station.