Abstract: Climate change which is a typical global issue has high externalities. Different countries and groups have different attitudes,so there are many criteria for evaluating climate policy,including environmental effectiveness,cost-effectiveness,intergenerational equity,interregional equity,institutional feasibility,technical feasibility,and ethics. In international climate negotiations,criteria for climate policy choice are often controversial. Firstly,developed countries emphasize the environmental effectiveness,while developing countries emphasize the cost-effectiveness. Secondly,developed countries and developing countries have the controversy about the funds and technology transfer. Thirdly,the target of controlling global temperature is a disputed issue about intergenerational equity. The perfect climate policy would satisfy all criteria. In other words,the perfect climate policy would take intergenerational equity,interregional equity,and ethics into full consideration,satisfy institutional and technical constraints,and achieve the environmental objectives at a minimum cost to society.