To compare the effects of the arc radius of different vertical breakwater crest walls on its wave load,we carry out the physical model experiment about the three arc crest walls with the arc radius of 45 cm,67 cm and 98 cm respectively and the vertical crest wall,and obtain wave loads from the integral of the wave pressures on different measure locations of crest walls. Then,we analyze the relationship between the wave load and the relative wave height,relative wave length and the arc radius. The research results show that the wave loads increase with the increase of the relative wave height and they present the variation trend of firstly increase-then decrease-finally increase with the increase of the relative wave length. For the same wave conditions,the wave loads on the arc crest walls are bigger than those on the vertical crest wall. Among the three arc crest walls,the wave loads decrease with the increase of the arc radius and the maximum occurs on the arc crest wall with the arc radius of 45 cm.