The Military Defence Circuit was an important local management institution in the Ming Dynasty. In order to contain the intrusion of “River thieves”, “Wokou” (Japanese pirates) and “Mining thief”, as well as to consolidate the local farming system, water conservancy, and other affairs, the Ming court successively established five Military Defence Circuits in Fengyang, Jiujiang, Taicang, Yingtian and Huirao from Hongzhi to Jiajing Reigns. Their scope of the jurisdiction cover both Anqing and Huizhou. During this period, the Military Defence Circuit's jurisdiction unit gradually changed from Wei to Fu (prefecture). In the sixth year of the Longqing Reign, out of the consideration of unifying administrative divisions, the Ming court set up the Huining Military Defence Circuit, which put Fu and Wei in Anqing and Huizhou under the same Military Defence Circuit's management, while remained under the jurisdiction of South Zhili. Later, due to changes in local situations, the Ming court made a series of differentiations and adjustments to the Huining Military Defence Circuit in order to keep it militarily advantageous. The evolution of the division and integration of the Military Defence Circuit shows the importance of local governance in Anqing, Huizhou areas. It would become one of the precursors to the formation of Anhui Province in the Qing Dynasty.