Controlling the amount of residual relative energy and the downstream Froude number is one of the important issues faced by designers of inclined drop structures. In this study, 120 different experiments were performed for three angles and two drop heights to investigate the effect of using gabion structure in inclined drop structure in comparison with the use of stilling basins downstream of this structure. The results showed that for all models, increasing the relative critical depth increases the residual relative energy. The amount of residual relative energy was significantly reduced when using the gabion structure in the inclined drop building and creating the gabion inclined drop. The gabion inclined drop reduced the residual relative energy of the downstream by 30%, 33%, 30% and 36%, respectively, compared to the type 1, 2, 3 and 4 stilling basins. The use of gabion inclined drop compared to simple inclined drop reduced the Froude number from 4.49- 8.35 to 1.28-2.64.
