The present invention is designed to provide a radio communication 
system, a user terminal and a radio communication method that make it possible to monitor 
communication quality adequately even when a new 
radio resource structure is employed. A radio communication 
system is provided, which transmits downlink control information from a 
radio base station to a user terminal by using an enhanced downlink 
control channel that is frequency-division-multiplexed with a downlink shared 
data channel, and which also monitors downlink quality based on the received quality of downlink reference signals that are transmitted from the 
radio base station to the user terminal, and, in this radio communication 
system, the user terminal determines 
radio link failures by comparing the received quality of the downlink reference signals transmitted from the 
radio base station, against one or both of first criteria, which are constituted of two thresholds that correspond to predetermined 
block error rates of a downlink 
control channel, and second criteria, which are constituted of two thresholds that are different from the two thresholds of the first criteria.