The present invention is designed to provide a radio base station, a user terminal, a radio communication method and a radio communication system of novel structures that can achieve improved throughput and system capacity. A radio base station transmits downlink reference signals that are specific to a plurality of transmission beams, a plurality of user terminals feed back coarse channel state information that is acquired by channel estimation, to the radio base station, the radio base station selects a plurality of user terminals to make feed back accurate channel state information based on the coarse channel state information, a plurality of user terminals that are selected feed back accurate channel state information, the radio base station determines a plurality of user terminals to non-orthogonal-multiplex, per transmission beam, based on the accurate channel state information, and non-orthogonal-multiplexes downlink signals, and a plurality of user terminals that are determined, after having canceled interference between the transmission beams by means of a linear filter, cancels downlink signals for other terminals, from the downlink signals that are non-orthogonal-multiplexed in each transmission beam.