On the basis of global climate change facts and the analysis of the national climate change action, identification of a few key issues and debate of different points of view of the current scientific understanding of global climate change and actions has been made. It is pointed that: ①as a start point, the relative reliable and certain scientific facts, as well as the principles of the common but different duty should be taken in order to response to climate change; ②the magnitude of global warming has been overestimated; ③over the past century warming is mainly due to human activities is lack of scientific evidence; ④effects of global warming pros and cons need a concrete analysis of specific problems; ⑤climate predictions does not equal weather forecasting and their uncertainty is very large; ⑥the current action to address global warming should be taken to “adapt the main mitigation supplement” strategy.