【Objective】Taking Fengdu county in Chongqing as an example, a dynamic monitoring sampling point arrangement system of cultivated land quality in southwestern mountainous area was built to provide references for cultivated land protection in southwestern mountainous area and cultivated land protection policy-making for territory departments in other areas of China.【Method】According to regional background analysis of the monitoring area，there were four partitions of natural quality, utilization level，economic level and land use characteristics in the background. Finally the supervised monitoring area was designated. The approach of one unit guiding a whole area was used to reflect the change trend of cultivated land quality of the overall monitoring area. 【Result】The study area was divided into 7 monitoring control areas，including 33 supervised monitoring areas. A total of 111 samples from the fixed monitoring points were distributed in different monitoring control areas with different cultivated land qualities and different land use types. Forty-two dynamic monitoring samples of 17 engineering activity areas were laid out. A dynamic monitoring and sampling control system of cultivated land quality was built. 【Conclusion】Designated monitoring control area conformed with land use and cultivated land quality distribution characteristics of southwest mountainous area, and it had the characteristics of homogeneity. Multi-information and multi-duration stereoscopic and long-term monitoring method was a more scientific and reasonable way for supervising cultivated land quality. It is more scientific to choose dynamic monitoring sampling spots based on land use project features in southwestern mountainous area.