To calculate the wave loads of closely spaced pile breakwater structure，we carry out the physical model test to do research on the wave load of closely spaced pile breakwater based on a breakwater project.The results show that the theoretical formula of wave load for vertical-walled structure can be calculated for the closely spaced pile breakwater structure，and the results of the OCDI formula is similar to the test results.The wave load along the axis of the closed-pile structure presents a trend of larger body and smaller head.Oblique waves have a certain influence on the wave load on the closely spaced pile breakwater structure，and the reduction coefficient of the OCDI formula can be used for approximate evaluation.