Climate change has significant impact on cities which usually are important social-economical centers with huge populations.This study reviewed climate change adaption actions in major meg-cities in the world，and suggested that disaster risk reduction management is the city’s primary task for adapting to climate change. Taking Shanghai as a case study，it shows that several climate factors，such as the frequent hot days，increasing heavy precipitation，rising sea levels，and reducing average wind speed，have increased climate change risks in several urban sectors，especially in energy，water，flood control，agriculture and atmosphere environment.This paper represents the Shanghai’s comprehensive climate change risk management practices which are based on the mechanism innovation，including institutional system，capacity building and popular science outreach.