We report a simple solution-processed method for the fabrication of low-cost, flexible optical limiting materials based on graphene oxide (GO) impregnated polyvinyl alcohol (PVA) sheets. Such GO–PVA composite sheets display highly efficient broadband optical limiting activities for femtosecond laser pulses at 400, 800, and 1400 nm with very low limiting thresholds. Femtosecond pump–probe measurement results revealed that nonlinear absorption played an important role for the observed optical limiting activities. High flexibility and efficient optical limiting activities of these materials allow these composite sheets to be attached to nonplanar optical sensors in order to protect them from light-induced damage.