PROBLEM TO BE SOLVED: To provide a water supply system capable supplying water to a plurality of rice paddies in a short time while suppressing excessive discharge.SOLUTION: A water supply system according to one embodiment includes: a first gate control device; a second gate control device; and a water supply control device. The first gate control device controls the height of a first irrigation channel gate which is on a downstream side of a first branch portion between an irrigation channel and a first offtake channel. The second gate control device controls the height of a second irrigation channel gate which is on a downstream side of second branch portion between the irrigation channel and the second offtake channel, on a downstream side of the first branch portion. The water supply control device outputs a control signal for bringing the height of the first irrigation channel gate to a first height to the first gate control device. Further, the water supply control device outputs a control signal for b
