The present invention provides a system for endoscopes which can supply air and water according to each application by regulating air and water flow rates independently. Although air and water may be supplied with one pump, the present invention controls air and water flow rates separately by using an air supply pump and water supply pump and by controlling a plurality of open-close valves installed, for example, on atmospheric escape pipes. The air channel and water channel are connected, for draining, by a first connecting pipe. If the air supply pump is used also for water supply and the water supply pump is used also for air supply, it is possible to supply air and water at a high flow rate fast enough even for high-speed water injection. If a fixed flow rate is used for a specified time at the start, specific operations can be simplified.