Climate change is a global issue and threatens the basic element of life for people around the world. Lots of countries have set up targets and take measures to mitigate carbon dioxide emissions. China has also set up its own target to reduce carbon dioxide emission per unit of GDP by 40%-45% in 2020 compared to the level of 2005. This thesis develops a framework to estimate the emission level of carbon dioxide at local (or city) level in China by scenario analysis. This framework is applied to Shanghai in order to find a feasible way to reduce carbon dioxide emission. This thesis sets up four scenarios (i.e. Business As Usual Scenario, Transformation Scenario, Moderate Intervention Scenario and Strong Intervention Scenario) to assess the activity level and energy efficiency in industrial, commercial, residential and transportation sector. According to the assumptions on economic growth, population growth and the changing trend of activity level, final energy consumptions in industrial, buildings and transportation sectors are calculated. Industrial sector has the largest contribution to total reduction amount, buildings sector is the second contributor and transportation sector has the smallest contribution. According to the assumptions on energy structure, carbon dioxide emission is estimated. Under BAU scenario, total carbon dioxide emission will reach 46172 (10 000 tons CO2), and carbon dioxide per capita will reach 19.93 tCO2/person in 2020. However, carbon dioxide per unit of GDP will decrease by 39% compared to the level of 2005, which doesn’t achieve the target. Under transformation and moderate intervention scenarios, total carbon dioxide emission and carbon dioxide per capita will be on the rise from 2010 to 2020, while carbon dioxide per unit of GDP will decline by 47% and 54% respectively. Under strong intervention scenario, total carbon dioxide emission will reach 26041 (10 000 tons CO2) in 2016 and then it will decline gradually. Carbon dioxide per capita is around 12.7 tCO2/person from 2008 and 2011, and afterwards it will be on the decline. Carbon dioxide per unit of GDP will decline by 58%, which achieve the target.This thesis also identifies countermeasures for Shanghai to mitigate carbon dioxide emission and classifies them as energy demand control, energy efficiency improvement and energy structure measures. The main countermeasures are to enhance energy efficiency, optimize energy structure, adjust industrial structure, set efficient and fast transportation system, and develop energy-saving technologies.