In this study, the effect of slurry application/injection methods and polishing conditions on slurry flow dynamics at the retaining ring bow wave was investigated. Two slurry application/injection methods (standard slurry application method and novel slurry injection method) were used. For each method, an ultraviolet enhanced fluorescence system was implemented to measure the slurry film thickness at bow wave for a polyetheretherketone (PEEK) retaining ring at different sliding velocities, slurry flow rates and ring pressures. Results indicated that the novel slurry injection method generated significantly thicker slurry film at the bow wave than that of the standard slurry application method. For both methods, slurry film thickness at the bow wave increased with increasing flow rate and ring pressure while it decreased with increasing sliding velocity.