The transportation sector in a city is one of the fundamental aspects of social – economic system which includes moving people and trade in an increasingly globalized world, as well as for improving standards of living. No doubt that transportation sector cannot be separated from the fuel consumption. Every country applied different policies and scenarios to introduce alternative fuel and technology to reduce the road transportation that is dependent on fossil fuel and the environmental impacts. However, in the last decade, global energy consumption in the transport sector was increased continuously. In the city context, transportation sector should be put on the long term urban planning toward sustainable development. The purpose of this study is to investigate the energy consumption and road emissions of the transportation sector to predict the future energy consumption and emissions interactions. A system dynamics model for transportation sector was developed in this study to model the transportation energy consumption and road emission trends. The basic data on energy consumption, transportation data and emissions factor were used as the basic input parameters. Results show that total fuel consumption and GHG emission in Padang road transport is predicted 65 times in 2050 compared to 2013 levels. Increase of private vehicles plays a very essential role in road emissions reduction activities of Padang. The modelling results also show that reducing of private vehicles and integrated public transportation has reduced the fuel consumption and GHG emission to about 34% in 2050. All these results will provide essential information and can be used for policy maker to meet challenges of decision making to support the urban development process.