Abstarct: Therefore, over many years in our country, water storage structures such as dams have been widely constructed. The most important problem that threatens such structures is the possibility of cavitation in areas where water flow is very fast. So far, severe cavitation damage has been discovered in major spillways around the world. In recent years, advanced and precise numerical methods have been used increasingly to design appropriately the complex hydraulic structures. In this research, Fluent software was used to investigate the cavitation phenomenon around the chute spillway. The modeling procedure was implemented through two different phases. In the first step, the modeling was performed with the aim of obtaining similar numerical and laboratory results to ensure the accuracy of software performance. The results of this step showed that the model made with Fluent software is in excellent agreement with the results of the laboratory model tests. In the second step, sensitivity analysis was conducted in addition to the main model (chute spillway with 36.4 % bed slope), 26 %, 30 and 40% bed slope combined with different bed roughnesses including 0.15, 0.4, 1.5, 3 and 5 mm. The results of parametric examination also showed that in the model with a bed slope of 26 % and 30 %, the probability of cavitation due to the roughness of elevation is low. In models with 36.4 % slope in some parts of chute spillway with higher roughness, probability of cavitation is lower than models with lower roughness. In the model with a 40 % bed slope for all considered roughness heights, the slope of the downstream side weir is located in the critical range of cavitation and the probability of cavitation is high at the 60 m end of the spillway.