The aim of this study was to determine the potential reduction on GHG emission from transportation sector, in particular from passenger cars (according to car figures in 2016). The GHG reductions were determined for different scenarios (1) current situation (2) to implement of the taxation system based on carbon emission (3) to make reduction on taxes (rate of 18% and 27%) and (4) to apply a regulation for End of Life Vehicles (ELVs) We found that the best scenario is to apply the regulation for ELVs. If the regulation is applied for banning vehicles which were produced before 2000, 1996 and 1990, the reduction rate of CO2 emission would be 48%, 36% and 26%, accordingly. The CO2 reduction rates in transportation sector calculated for different scenarios will change approximately 2% to 15%. Consequently, the total GHG emission reduction in Turkey will be about 0.2% to 2%.