With the effect of the lockdown policies that have appeared during the Covid-19 pandemic period, various socio-economic effects have emerged that limit the daily activities of people. While the effects of Covid-19 have had a negative impact on many sectors, a decrease in certain sectoral activities has affected environmental factors positively, as in the case of road transport. This is because, during the Covid-19 pandemic, people's use of private vehicles has decreased. In the current paper, the environmental effects of Turkish road transportation fuel consumption are investigated in the lockdown period experienced due to the Covid-19 pandemic. For this purpose, the production of greenhouse gas emissions (GHG), their global warming potential (GWP), and social costs were estimated, dependent on road transport fuel consumption data corresponding to the months of January and October from 2017 to 2020. Because the Covid-19 lockdown process in Turkey an important were a good opportunity for the detection of road transportation-induced GHG emissions, and their effect on the enviro-economic indicators. According to the main findings of the study, the consumption of road transport fuels decreased significantly in the first 2 months following March 2020, (April and May), when the first Covid-19 case appeared in Turkey. On the other hand, GHG emissions, their GWP, and social cost values decreased, also dependent on the decrease in fuel consumption values for this time period.