Abstract: The Chongqing Military Grounds was where three troops directly under the Chongqing Military Command trained in the Qing Dynasty. In consequence of the institutional economic predicament of Green Standard Army, the location gradually changed from a military training ground to a market during the expansion of urban commercial space in Chongqing. Between the later years of the Kangxi reign and the early years of the Yongzheng reign, the common people and the officers and soldiers of Green Standard Army who were forced to do something to make a living began to encroach upon the government’s land of and build houses and shops on it. In view of the adverse effect of theoccupation of the land on military training, the principal of Chongqing Military Command took the action of cleaning up the occupied land. In the twelfth year of the Jiaqing reign (1807), the principal of Chongqin Military Command rented out the space to repay the debts owed to officers and soldiers and subsidize the soldiers’ monthly rice consumption. Since then, the area was completely reduced to a commercial market that was occupied by people in various trades. The officers and soldiers of the three troops directly under Chongqing Military Command lost their basic military training ground during the transformation from a military training field to a trade market, and this had an irreversible impact on the decline of their combat effectiveness.