Abstract: The fringing reef is a special coastal topography. Many scholars at home and abroad have studied the propagation and deformation of waves on the fringing reefs, but few have studied the revetment engineering on the fringing reefs, hence lack of understanding of the key design parameters. For this reason, taking the revetment project of the Maldives Airport island as an example, some analyses and studies of the stability of the armor blocks under the conditions of three different bank widths, four different water depths and wave combinations are carried out through the physical model test in a 1:10 scale wave flume. The test results show that the bank width, that is, the distance between the toe of the riprap revetment slope and the reef edge, is an important factor affecting the stability of the riprap revetment. Under the same water depth, wave condition and weight of the revetment blocks, the instability rate of the revetment blocks decreases with the increase of the width of the bank slope. Further analysis of the test results shows that in order to ensure the safety of revetment, the toe of slope outside the riprap revetment should be placed behind the breaking point of wave, and the distance between the toe of the slope and the breaking point is recommended not to be less than 0.26 times the shallow water wave length of reef flat T \sqrtg h_\mathrme . This key design parameter has important guiding significance for the design of similar bank protection works in the future.