A 30 years experiment was altered and soil aggregates,bulk density,porosity and mean weight diameter(MWD）were measured to determine the effects of followingup fertilization reforming on soil aggregation of reddy paddy soils cultivated under different seven fertilization treatment,i.e.high organic material(HOM),normal organic material(NOM),chemical fertilizer(CF),normal organic fertilization treatment changed from chemical fertilization treatment(CN),chemical fertilization treatment changed from original normal organic fertilization treatment(NC),chemical fertilization treatment changed from original high organic fertilization treatment(HC),high organic fertilization treatment changed from original normal organic fertilization treatment(NH),which in order to select a reasonable followup fertilization strategy for cultivited reddy paddy soils and provide theoretical basis for promoting the sustainable development of paddy soil.The results showed that organic fertilization（HOM，NOM）had greater ability to decrease soil bulk density by 10.38%~19.81% and improve soil porosity by 6.77%~13.13% and MWD by 46.84%~6158% compared with chemical fertilization（CF）.It was the coarse macroaggregate(> 2 mm）which having the highest ratio among soil aggregates under organic fertilization treatments（HOM，NOM，CN，NH）,while it was the fine macro aggregate(2~025 mm）under chemical fertilization（HC、NC、CF）. After 3 years followingup fertilization alteration， reducing the input of organic fertilizer（HC、NC） would increase soil bulk density （6.47%~14.34%）,decrease soil porosity（3.63%~6.79%） and MWD（21.15%~31.43%）. while increasing input of organic fertilizer （CN，NH）would decrease soil bulk density（308%~902%），increase soil porosity （1.73%~6.01%）and MWD（5.45%~44.58%）.As a conclusion,the followingup organic fertilization was necessary to maintain or improve soil aggregation in the longterm cultivited reddy paddy soils with high fertility.