The organic carbon in soil aggregates plays an important role in the dynamic balance of soil carbon pool.In order to explore the impacts of digested dairy slurry application on soil aggregates and their organic carbon composition,this study was carried out in a wheat and maize rotation system applied with digested dairy slurry for two years.The characteristics of soil aggregates and their total organic carbon and compositions in soil layer of 0-10 cm and 10-20 cm were studied after harvest.The results were that the stability of soil aggregates increased significantly (P<0.05) after the digested dairy slurry application.The digested dairy manure was beneficial to the improvement of macro aggregates.Meanwhile,this trend was more obvious with the increase of the amount of digested dairy slurry.The soil carbon stock in the treatment of digested dairy slurry application increased by 25.9%-35.2% compared with that in treatments of chemical fertilizer application.The changes of soil carbon stock were mainly due to high-activity organic carbon.The soil carbon pool activity was improved due to the input of labile carbon in the digested dairy slurry.In addition,the soil carbon pool activity in the soil layer of 10-20 cm was more sensitive to the input of additive organic matters.The highly active organic carbon in the macro aggregates was the main drive factor.This study could provide scientific support for the reasonable application of digestates for the improvement of carbon sequestration potential from the farmland ecosystems.