Abstract: In this paper, we'll report the experimental results on the KrF laser-induced coating damage studied by the photo-acoustic method. The experimental results show that the ZrO₂/SiO₂, coating had a damage threshold less than lJ/cm² and had a different shapes of the photo-acoustic signals before and after damage. The reason of the coating damage is the large absorption coefficient of the ZrO₂, layers in the coating.