Waiting time has a negative impact on resource use and the medical quality of surgical rooms, with those hospitals which have implemented quality management may have found difficulties sustaining their programmes, however, there is significant variability in their success. In this paper, we used Six-sigma method to examine the improvement of time efficiency in surgical rooms. This method was applied to a hospital with 11 surgical rooms and 820 sickbeds. The clinical data for the five exclusive time intervals are collected, analysed, and continuously improved. The results showed that a standardised surgical process can reduce the total waiting time, and the proposed Six-sigma method may reduce variations in surgical room process. Finding presents a comprehensive model encompassing research work and a holistic insight of improving patient satisfaction and healthcare quality.