The stability of armour layer on the breakwater has been studied and the result is reviewed in this paper. By undertanding the stability of armour layer on the breakwater due to wave attack, it could minimize the breakwater damage and maximize the armour layer performance as a breakwater protector. The armour stability on composite breakwater has been investigated by 2-D physical model experiments using regular waves, combining with theoretical approach and field data application of South Java coastline, Indonesia. Tetrapods are used as armour layer for the breakwater. The breakwater model was placed inside a wave flume. The result shows that the level of damage was affected by wave characteristics of wave steepness. The steeper the wave steepness, the armour layer profile will change. It is shown by the percentage of the number of displacement and movement number of armour unit from its initial position, or armour layer damage under design wave. The results conclude that the results of physical models study can be used as a reference for the design of armour layer on breakwater.