The invention relates to a cleaning and sterilizing system of a drinking liquid filling device, at least comprising a filling machine, a capping machine and a conveying chain for conveying bottles. The cleaning and sterilizing system comprises a cleaning agent and bactericide preparation device for preparing cleaning agents and bactericides, a plurality of nozzles which are respectively arranged on multiple positions of the filling machine and the capping machine and used for cleaning and sterilizing the environments of the filling machine, capping machine and peripheral devices, a connecting line which is respectively provided with the nozzles and connected with the cleaning agent and bactericide preparation device, a pressure device for providing pressure for the connecting line, a control device which is electrically connected with the cleaning agent and bactericide preparation device, the nozzles and the pressure device to control the preparation and storage of cleaning agents and bactericides and spraying action, time and intensity of the nozzles, and an anti-splash device for preventing the cleaning agents and bactericides from splashing in the bottles in the process of cleaning and sterilizing.