Abstract: To address the issue of the difficulty in accurately predicting the fuel evaporation emissions from vehicle fuel tanks， a study on the simulation of the fuel evaporation process and the prediction of evaporation volume was conducted. A fuel evaporation test platform was constructed， and fuel evaporation volume tests were carried out under different fuel components， environmental temperatures and pressures. Based on the vapor-liquid equilibrium（VLE） theory， a simulation model of the fuel evaporation process was established to numerically simulate and analyze the fuel evaporation behavior in the tank. The results showed that this model could well reflect the evolution laws of the fuel evaporation process in the tank. The prediction errors for the main components of the evaporated fuel， namely isopentane， n-butane， methyl tert-butyl ether， and n-pentane were 0.2%， 4.6%， 11.4% and 0.9%， respectively. And the prediction error for the total amount of fuel evaporation emissions did not exceed 3.02%. The research results indicate that the established model can effectively predict the fuel evaporation volume of vehicle fuel tanks and provide a theoretical basis for the optimization design of the evaporation emission control system.