The problem of massive emissions of carbon dioxide (CO2) from the burning of fossil fuels and their climatic impact has become major scientific and political issues. Electricity generation, transportation, industrial and residential are the main sectors identified to contribute to the emission of CO2 in Malaysia. In this study, a comprehensive modeling tool, long-range energy alternatives planning system (LEAP) was utilized to project CO2 emissions from year 2000 to year 2020 for each sector. It was projected that without any mitigation measures being taken up by the country, 285.73 million tonnes of CO2 will be released in 2020, which is a 68.86% increase compared to the amount of CO2 emitted in year 2000. Electricity generation, which gives 43.40% out of total of emissions, was discovered to be the largest emitting sector among all sectors. In addition, this study also reviews recommended mitigation analysis proposed by other researches as well as implementation of energy efficiency program in Malaysia. This projection and mitigation is a hope to provide an important basis to reduce future CO2 emissions and their associated impact in Malaysia. © 2010 American Institute of Chemical Engineers Environ Prog, 2010.