Abstract:To explore the influence of dry-wet cycles on soil aggregate stability in Southwest China, an experiment was conducted in the Jinyun mountain in Chongqing. A typical yellow soil in cultivated land was taken as the research object. With four groups of aggregates of different particle sizes (1-2, 2-3, 3-5, and 5-7 mm) , seven dry-wet cycle processes (1, 2, 3, 5, 7, 10, and 15 times) under four antecedent moisture levels (air dried, 10%, 15%, and 20%) were simulated. The stability?features of soil aggregates after dry-wet cycles under different broken mechanisms were discussed with the Le Bissonnais method. The results showed that: (1) Fast wetting (FW) had the most serious damage on soil aggregate stability, and there was a significant difference between FW and the other two broken mechanisms (slow wetting (SW) and stirring (ST)). (2) Compared with large-size aggregates, the stability of small-size aggregates was higher. (3) The destructive effect of dry-wet cycles on aggregate stability was obvious, and the extent of the damage was different under different antecedent moisture levels. (4) The dry-wet cycle processes mainly affected the stability of aggregates by affecting the percentage of >2 mm aggregate fragmentation. These results had an important reference value for the study of soil erosion mechanisms in Southwest China.