Coming from the transactions, the agents have been becoming the leading role in the modern international trade. As one of the fastest growing economies in the world, there have been taken great place in foreign trade of China, so there is some requirements to discuss the problems on agency law. In this thesis, I focus on the agency law in the international trade. I use the comparative method to discuss the differences of Civil law and Common Law, and analysis two international conventions that are important in the agency law system. On these bases, I discuss the agency system of foreign trade in China, and give some advice to reslove the problems in agency system. I explore some types of special commercial agent in the external trade, especially analysis the factor agent characteristic, and raise my viewpoint.