Residual stresses are those remaining in mechanical parts free of any external loading. They generally come from thermal effects, mechanical loading and/or metallurgical phase transformation during the manufacturing steps. When these stresses are of tensile type, they can have negative consequences on the lifetime of the component by helping cracks initiation and propagation phenomena like Stress Corrosion Cracking (SCC). In order to improve the fatigue life and avoid the premature failure of metallic components, surface treatment processes are carried out to introduce residual stresses of compression in materials and to raise the critical value of operating tensile stress. Conventional Shot Peening (SP), Ultrasonic Shot Peening (USP) and Laser Shock Peening (LSP) are some of these surface treatment methods which have been widely studied both experimentally and numerically. Water Cavitation Peening (WCP) is a similar process of surface treatment [1]. During WCP, cavitation bubbles are created by a high-speed submerged water jet directed toward the workpiece surface. The cavitation phenomenon occurs in low static pressure (lower than vapour pressure of water) zones due to the turbulence generated, at a given temperature. The collapse and/or the impact of these bubbles on the treated surface induce high loading pressures and thereby plastic deformation of the superficial layers of the material. Superficial compressive residual stresses are then introduced in the material. This process is known to provide a better surface finish with less roughness than that of the conventional shot peening because there is no solid-solid contact involved [2]. Many experimental studies have proven the efficiency of the present process to introduce compressive residual stresses into relatively high yield strength materials and enhance their fatigue strength [3]. However, the modelling of cavitation peening is very challenging, because of the complex behaviour of cavitation phenomenon. Very few studies concerning the modelling and simulation of WCP have been reported. A mechanical model based on finite element method have been proposed by Han and Hu [4] to predict the residual stress profile obtained after WCP. The authors measured experimentally the affected surface diameter. Then, they supposed a constant spatial distribution and trapezoidal temporal variation, for the loading pressure. As the above-mentioned study, most of the numerical studies about the modelling of cavitation peening employed theoretical values for pressure magnitude and pressure pulse duration with no direct link to the process parameters. The main reason and issue is the difficulty to determine the impulsive pressure distribution of cavitation peening.