This article figures out the economic impacts on macroeconomy, industrial output, new energies and environment when the advantageous bioethanol and its feedstock production increase and replace the usage of gasoline in the future. A CGE model, called ¡§Taiwan General Equilibrium Model-Energy, (TAIGEM-E), was a linear/dynamic, linearized percentage change simulation tool used especially in the economic evaluation of environment policies. Results indicated that macroeconomic and environmental variables will all benefit with scenarios. Government should instantly encourage the production of bioethanol (and biodiesel) and it¡¦s producing resource because it truly can reduce the pressure of CO2 emission mitigation, and also can active agricultural fallow lands. It is an important long term issue.