With the second national land survey carried out, land grading method is nearly mature, but change monitoring of cultivated lands level has not yet been proposed an effective method. The paper makes the second national land survey as research basis for change monitoring. According to the differences of indicator monitoring periods, authors introduce the concept of volatile indicators. Change monitoring indicators are divided into volatile and non-volatile indicators. This way updates non-volatile indicators only when monitor can improve the efficiency of monitoring. For the region data is missing, this paper suggests filling the missing data through spatial correlation. In order to unify monitoring units, authors propose a new method- Be post-grading units as monitoring units, convert pre-grading values to post-grading units by area-weighted. Finally, we analyze the monitoring result by calculating the quantity, quality, layout, production levels and other aspects. The analysis will play a role in early warning for the quality of cultivated land.