The ring speed ratio of floating ring bearing is an important performance index which affects the power consumption and temperature rise,and the stability and reliability of the rotor bearing system.An experiment was designed to measure the floating ring speed and ring speed ratio of the floating ring bearing,with water as lubricant and under the shaft speed ranges between 1 000 r/min to 10 000 r/min,the load of 45 N and 75 N respectively.The effects of shaft speed on the floating ring speed and ring speed ratio were investigated.The experimental results show that floating ring bearing can effectively reduce the relative speed between the journal and the bearing,and there is nonlinear relationship between ring speed ratio and shaft speed.Under the heavy static load condition,the ring speed ratio is decreased rapidly with the increasing of shaft speed,which indicates there is a need for further optimization to maintain a stable ring speed ratio.Under the light static load condition,the ring speed ratio is increased with the increasing of shaft speed,which indicates the floating ring bearing is more suitable for using at high speed light load condition