In this study the effects of levying various green taxes (base, 5%, 10% and 20%) on Iran’ s fossil energy consumption (oil gas (OG), natural gas (NG) and gasoline (GA)), pollutant gas emission and social welfare was studied using a Recursive Dynamic Computable General Equilibrium (RDCGE) model. In order to RDCGE calibration, the Iran’ s social accounting matrix (SAM)) and base scenario was used. Required data was gathered from central bank of Iran (CBI), Iran’ s statistic center and ministry of energy during 2008-2016 seasonality. Also, for data analyzing Matlab software was applied. Results indicate that in while increasing green tax, a positive shock of economic growth (1%), reduces the increasing trend of OG, NG and GA. Also, levying 0% and 5% green tax couldn’ t make the consumption of mentioned energies efficient, levyeing 10% green tax makes the consumption of NG and GA efficient and levying 20% green tax makes the consumption of mentioned energies efficient. In addition, while increasing green tax, a positive shock of economic growth (1%), reduces the increasing trend of gas pullotants emission and in orther to decreasing gas pollutants emission during economic growth, 10% green tax should be levy. Finally, while increasing green tax from 0% to 5%, 10% and 20%, a positive shock of economic growth (1%) increases the social welfare, less than 1%, more than 1% and less than 1%, respectively. Therefore, between studied scenarios, levying 10% green tax is the best for increasing social welfare.