Abstract: Objective: To study the influence of biofeedback on voltage variations of the external anal sphincter （EAS） for the old patients suffering from soiling. Methods: Using the products of CTD company-biofeedback machine （PC POLYGRAM）, with the help of the muscle electronic signals and language feedback of the operator, the six elderly suffering from soiling participated in the process of rehabilitation of anorectum.Results: Through an average of six sessions of biofeedback training, the effects of this method had a significant relation with the mean values of voltage in the states of squeezing and relaxing of the EAS. There presented a good results with the elevation of squeezing voltage and relaxing one.Conclusion: Through short period of biofeedback training for the elderly with soiling, the voltages of EAS in the states of squeezing and relaxing elevate significantly, which is beneficial for the anal control.