Yunnan, located in the southwest border area of Mainland China, came under the influence of Southeast Asia regarding its form of currency. In addition, Yunnan's development of commodity economy was also slower. This caused the natives of Yunnan to use cowry shells as a medium of exchange. They actually did not use copper coins from the interior of China for a long time. The Government tried to execute the nationally consistent Note Law during the Yuan Dynasty and the Ming Dynasty's early stage. After the Ming Dynasty's intermediate stage, the government planned to cast copper coins and supply them for circulation in Yunnan, but its success was quite limited. Confronted with the special currency culture, the government tried to increase its economic influence by gradual and compromising policy, and took advantaged of the currency price difference to raise financial income. During the Ming Dynasty's last stage, the commodity economy grew considerably. In addition, the economic and trade environment of Southeast Asia fluctuated. These transitions resulted in the gradual reduction of cowries being used in the Yunnan region as a medium of exchange. Silver and copper coins gradually replaced the function of shell money.