As the European Union and North American countries have successively developed strict carbon tariff systems，the “carbon label” is likely to become the passport for international trade. Therefore，more and more companies attached importance to the carbon label system，and actively plan for the launch of their carbon label system. Many multinationals have introduced sophisticated carbon label systems. This report selects four well-known multinational companies that are relatively mature in implementing the carbon label system. They are Evian，Quorn Foods，Unilever，and Tetra Pak. It is found that the implementation of the carbon label system of the four multinationals has reduced their carbon emissions，saved enterprise costs，promoted sustainable development，and led to other aspects of the remarkable effects. This report can provide a reference for Chinese enterprises.