In the fourteenth year of Hongwu (138 1), in September of the lunar calendar, Zhu Yuanzhang took Fu Youde as the general and Aquamarine and Mu Ying as the deputy generals, and led 300,000 troops to conquer the remnants of the Yuan Dynasty in Yunnan. Zhu Yuanzhang personally arranged the marching route, and Mu Ying and Fu Youde advanced, forcing Qujing Hongwu fifteenth year (1382) to leap in February, and Mu Ying and Aquamarine led the troops to attack Dali in the west.

In the fifteenth year of Hongwu (1382), in July of the lunar calendar, Mu Ying led his troops back to Dianchi Lake, joined forces with Fu Youde, settled Wusha, Dongchuan, Jianchang and Mangbu separately, and set up two guards in Wusha and Bijie.

In the fifteenth year of Hongwu (1382), in September of the lunar calendar, when Fu Youde and Mu Ying led the troops to conquer some areas again, the local official Yang Mao dispersed the Ming army, moved his troops back to Korea, and assembled 200,000 rebels to attack Kunming. At that time, Feng Cheng (son of Feng) was guarding Kunming. Kunming is short of food, and most of the soldiers are sick and the situation is critical. When Mu Ying heard the news, he led his troops back to Kunming, joined forces with Feng Cheng, defeated the rebels, beheaded 60,000 people, held Kunming, and stabilized the situation.