Abstract: A preparation method for an ultraviolet-responsive coumarin controlled-release and self-repairing anti-fouling paint includes: reacting double-end-group reactive polydimethylsiloxane, polyisocyanate, and an organic diluting solvent; adding a dihydroxycoumarin compound, a cross-linking agent and an organotin catalyst; adding a simple coumarin compound, and irradiating the mixture with 365 nm ultraviolet light to obtain the anti-fouling paint. An anti-fouling coat formed by the paint of the present invention has the advantages of controllable release of a coumarin green anti-fouling agent in response to external ultraviolet stimulation and self-repairing, and the problems that the release of the conventional anti-fouling agents in the anti-fouling coat is difficult to control, and that the low-surface-energy anti-fouling coat is difficult to repair after being damaged are solved.