Laser-induced damage in the nanosecond domain has been assigned to the heating and breakdown of local defects within the thin film and the various interfaces. Within the femtosecond regime, the damaging events can be traced back to multi-photon based excitation into the conduction band. When exceeding a critical electron density, a optical breakdown will occur. In this letter we report on evidence that two-photon absorption also significantly triggers laser-induced damage in Ta2O5 thin films at 532 nm and 8 ns pulse duration. For experimental verification, single layers of Ta2O5/SiO2 mixtures have been analyzed.