This paper presents a direct simulation of wave effects on oil spreading. A multiphase Lagrangian model has been developed for this purpose. The model solves the 2-D Navier-Stokes equations using the Smoothed Particle Hydrodynamics (SPH) method which is a fully Lagrangian meshless method. The new features of the developed SPH model are the ability of simulating oil, water and wave breaking directly. The model has already been verified for two-phase and free surface flows comparing results of the model with analytical solutions and with the results of some available numerical and experimental test cases. Here, this model is used to simulate the oil spreading under the effects of waves and near a floating boom. The effects of evaporation, emulsion, and dissolution, which are long-term processes (in hour or day scale) in oil spill fate, are not considered here. In the practical modeling of oil spills, this model can be used for near shore areas.