Wave transmission at low crested and submerged breakwater will affect the wave height in the harbor. 2-D and 3-D tests on the wave transmission ratio in the harbor are carried out for different arrangements. The results show that the wave transmission ratio attenuated with the distance away from the breakwater under the oblique wave action, and is less than the values in 2-D test when the sites are far away from the breakwater. Also, the wave transmission ratio will be decreased in the harbor as the wave transmission range of the breakwater is reduced. The paper puts forward some suggestions on the engineering design.