The climatic change convention is a matter of grave concern to the whole world. As a countermeasure against the climatic change convention, the Korean Government permits the sale of diesel passenger cars since 2005. In this paper, we analyse the effect of the sales permission of diesel passenger car as the countermeasure. The share, carbon emission, and pollutants emission of each type of passenger cars are analysed using system dynamics. The result is that the carbon emission is decreased by $5.5\%$ but the pollutants emission is increased by $5\%$. If the pollutants emission was dealt successfully with, the sales permission of diesel passenger cars would be a good countermeasure against the climatic change convention.