Jet electrochemical milling (jet-EC milling) is a promising technique to machine hard-to-cut metallic materials with high machining efficiency and flexibility. The process of the jet-EC milling of Ti-6Al-4V Alloy is difficult to predict due to the interaction of multiple physical fields and the formation of passivation film. In this work, a novel model is established to simulate the jet-EC milling and predict machining profile. In this model, the interactional relationships among electric field, two-phase flow field, and geometry deformation are considered using a multiphysics approach, and the breakdown process of the passivation film is involved for accurately predicting the machining results. In addition, the passivation film breakdown process of Ti-6Al-4V alloy is studied experimentally. Finally, several experiments on the jet-EC milling of Ti-6Al-4V alloy are conducted to verify the simulation results and discuss the influence of the travel rate on the material dissolution. The current density distribution on the anode surface is clarified. The proposed model is more in line with the experiments. By applying an appropriate travel rate, a sharp edge is obtained without stray corrosion as the electrolyte forms an upward reflection and the un-machined surface is free from stray corrosion due to the absence of the electrolyte.