Structure and stability of soil aggregates in upland red soil were studied in a long-term fertilization experiment. Results show that in treatments of mixed application of organic and inorganic fertilizers, bulk density of the soil decreased and porosity of the soil increased to some extent as was compared with that of blank treatment (CK).The percentage of mechanical-stable macroaggregates (>5 mm), increased by 2%〖KG-*3〗~42% as a result of application of organic manure.In terms of percentage of water-stable aggregates (>0.25 mm) the treatments followed a decreasing order of Stable manure>Rice straw>Green straw>incorporation of aerial parts>CKThe treatments of organic manure increased the contents of organic matter, amorphous Fe, and amorphous Al by 9%~54%, 8.5%~21.7% and 10.9%~26.8%, respectively over the treatments of application of chemical fertilizer alone.Statistic results show that the content of water-stable aggregates (> 0.25 mm) was significantly and positively correlated to content of organic matter (p<0.01), but soil aggregate destruction rate was significantly but negatively correlated to it (p<0.01). Application of organic manure in addition to inorganic fertilizer was not only favorable to formation of macro-aggregates in upland red soil, but also beneficial to improve structure and stability of the aggregates in the soil.