Disclosed is a method for supplying hydroxyl radical-containing water, which is highly convenient and with which water containing a relatively high concentration of hydroxyl radicals can be supplied to the point of use. The method for supplying hydroxyl radical-containing water comprises a production step of producing hydroxyl radical-containing water by dissolving ozone, hydrogen peroxide, and at least one additive substance selected from a group consisting of a water-soluble organic compound, an inorganic acid, a salt of an inorganic acid, and hydrazine in pure water, a transferring step of transferring the produced hydroxyl radical-containing water to the point of use, and a supplying step of supplying the hydroxyl radical-containing water to the point of use after transferring.