Abstract: In the face of the border defense oppression by the Mongols who were always eyeing covetously and the Nuzhen tribes who frequently led off an attack since the middle and later periods, the ruling class of the Ming Dynasty basically had a consistent view of the Great Wall, that is, affirming the idea of building the Great Wall, affirming the effective restriction and blocking effect of the Great Wall on the enemy, and building walls widely to strengthen the border defense, even if there were some different voices. Finally, it is also unified in the side policy of strict prevention of “Hu Rupp”. In practice, the Ming rulers adapted to local conditions and built the Great Wall that stretched for thousands of miles, forming a trend of supporting and supplementing the geographical space and military defense functions of the nine major military towns, which became the pioneering work and scientific experience of the Central Plains Dynasty in coping with the crisis of the northern nomads moving south for more than two thousand years.