A method is provided forwarding ozonated water efficiently with the loss of ozone lowered. The method for forwarding ozonated water is from an ozonated water producing device to a use point separated from the device. This enables the use point to be supplied with ozonated water having a concentration adjusted as aimed at, by adding a diluting water to a raw material ozonated water in the neighborhood of the ozonated water producing device under a condition inhibiting exposure to an ambient air, adjusting the amount of the diluting water to be added thereby giving the ozonated water a target concentration at the use point, and subsequently guiding the ozonated water through a pipe to the use point.