In this study, we argue the implementability of the Kyoto Protocol. It is estimated that the Japanese economy should have had reduced the emission level of the air pollutants by 23.4% less than the actual level in 1997 in order to clear the standard given by the protocol and we show how much we could reduce the emission of the air pollutant ( CO₂ , SOx and NOx ) in 1997. We present an input-output model which determines the optimal level of economic activities and their optimal emission of air pollutants so as to maximize the welfare function being subject to the emission standards of the air pollutants with respect to the emission taxes. And we formulate a model of the total environmental economic system which controls the air pollutants emitted by not only industries but also households. The fundamental of the model is the nonlinear dual system of the input-output analysis. It is shown in this research that the emission taxes themselves alone are not so effective for sufficient reduction in the emission of air pollutants contrary to the advocacy and technological progress in the abatement of air pollutants is needed to clear the Kyoto Protocol.