Abstract: The conflict between climate change and international trade has entered into WTO. Canada-feed-in-tariff was the first case about conflict between climate change and global trade. According to the reports issued by DSB,under the rule of WTO subsidy policies implemented by governments covering subsidizing entities,fiscal assistance and benefit analysis cause lots of disputes. From the perspective of climate change response,subsidy is vital for climate change mitigation. In order to implement subsidy rule about climate change without violation of WTO rule,subsidy rule under WTO should be reformed.