Abstract: Objective: To compare one-man method and two-men method in the operation of colonoscopy,and to assess its clinical value.Methods: Nine hundred ninety two cases examined with two-men method and 1 451 cases with one-man method were analyzed and the results were compared in terms of successful rate,operation duration,the rate of abdominal pain and the occurrence of enterobrosis.Results: The successful rates of one-man method and two-men method were 96.4% and 90.8%(P<0.005),respectively;the operation durations of that were(18.4±6.9) minutes and(26.6±8.3) minutes(P<0.001),respectively;the rates of serious abdominal pain of that were 1.0% and 6.7%(P<0.005),respectively;and the rate of enterobrosis were 0 and 0.3%(P>0.05),respectively.Conclusions: Compared with two-man method,one-man method is easier to operate and has a higher successful rate,shorter duration and a lower rate of serious abdominal pain.Therefore one-man method is worth popularizing and should gradually replace two-man method in colonoscopy.