Cavitation and choked flow conditions can occur when high-pressure drops are encounters in various types of valves, which prevent them to work properly and may cause severe erosion damage inside the valves that decrease their lifetime. Prediction of these critical conditions leads to the prevention of cavitation and helps to improve the design of the valve geometries to delay and prevent these critical flow conditions. Computational Fluid Dynamics (CFD) is a powerful tool that can be used to simulate flow conditions and to predict the incipient of cavitation and consequently choked flow in the valve through solving the Time Averaged Navier-Stokes equations under multi-phase flow conditions. Therefore, CFD simulations have been conducted for two types of excess flow valves. The mixture multi-phase flow solution method along with the k-ε realizable turbulence model has been utilized to solve the behavior of vapor flow inside the valve and simulate the cavitation phenomenon. It was observed that CFD could capture the inception of cavitation and choked flow inside the valve successfully. Simulated CFD results also indicated a good agreement with experimental data that were obtained under lower pressure drop conditions. The effects of various inlet pressures on the cavitation intensity have been also studied, and it was concluded that at higher inlet pressure with constant pressure outlet the cavitation strength is greater than lower inlet pressures.