The paper concludes the characters of methanol as a fuel in engines. Based on the kiva3v program, it conducts the multidimensional numerical simulation of the operation process in cylinder of a methanolfueled engine to obtain the detail information and performance graphic charts, as well as the real time data of pressure, temperature and so on. It is helpful for the research on methanolfueled engines. The results indicate that the methanol is a green alternative fuel and the methanolfueled engines have steady operations and lower emissions by comparing the numerical results with the data of gasoline engine.