There are three main reasons for this phenomenon. In fact, at that time, the Qing army entered the customs, because it was a foreigner, so the Qing rulers at that time did not lay hands on the imperial tombs of the Ming Dynasty. Not only that, they also sent people to protect the imperial tombs of the Ming Dynasty. The reason of 1 is the social situation at that time. The tomb of the Qing Dynasty was stolen during the Republic of China. Due to frequent wars, the number of warlords has increased dramatically. At that time, these warlords didn't really have much money as military expenses, so in order to ensure their military expenses, they could only look at the funerary objects in the mausoleum of the Qing emperor. The most typical example is that Sun Dianying excavated the tomb of Empress Dowager Cixi in the name of military exercises. Because the slogan of expelling Tatars and restoring China is deeply rooted in the hearts of the people, Sun Dianying's approach has also won the support of the people. The second reason is that it is difficult to dig secretly. Most of the Ming tombs were buried deeply. If grave robbers want to dig The Ming dynasty emperors's grave, it will be very difficult and it will take a long time. However, the burial depth of the imperial tomb in the Qing Dynasty was relatively shallow, and at that time, the world knew that Empress Dowager Cixi lived in luxury, so it was inferred that there would be a large number of funerary objects in the mausoleum after his death. At that time, the Qing emperors obviously had tombs that were relatively easy to dig, and there were many cultural relics waiting for grave robbers to dig, so grave robbers naturally didn't want to dig The Ming dynasty emperors's mausoleum. The third reason is that the treasures of the tombs of the monarchs in the two dynasties are very different. The main purpose of Sun Dianying's choosing to steal the Empress Dowager Cixi's mausoleum is actually for the funerary objects in the Empress Dowager Cixi's mausoleum. So are these grave robbers. When they choose the tombs to visit, they will first consider which tombs have more funerary objects and great value. Obviously, at that time, the funerary objects of the rulers of the Qing Dynasty would be more valuable, so grave robbers rushed to dig the tomb of the Qing emperor.