Marine energy is one of the most exciting emerging forms of renewable energy. Tidal turbines are used to extract this energy and installed on the seabed at locations with catastrophic loading. The present paper employs the finite element method to simulate the behavior of GRP composite nozzle of a tidal turbine under low-velocity impact with implementation of a failure criterion. To investigate this situation, a parametric analysis is conducted which deals with the effect of velocity, energy and geometry of the impactor. The mechanical behavior has been analyzed as both kinematic effect due to deflection of the composite structure and dynamic effect caused by the interaction between the impactor and the hydrodynamic and hydrostatic pressures over the loading. The stress and the deformation distribution are presented. On the other hand, damage modeling was formulated based on Hashin criteria for intra-laminar damage. The effects of the impact velocity and the panel’s flexibility on the initiation and propagation of damage have been investigated.