The soil aggregate and micro-aggregate of fixed fertilization plots in Qia nxian county, Shaanxi province are studied. The results showed that the disparities were remarkable in content of soil organic,matter, the quantity and proportion of each grade of aggregate and micro-agg regate in different fertilization,levels. Compared with the contrast, raising the level of fertilization, soil organic matter, 10-250μm microag,gregate and > 0. 25mm aggregate increased constantly, and the quantity of < 10μm micro-aggregate had the decreasing trend. Soil coefficient of disperse decreased and that of the soil structure increased.Analysis showed that the content of organic matter was positively linear corelated to quantity of > 0. 25mm aggregate and 10-250 μm micro-ag g reg ate respectively, and was neg atively linear corelated to < 10 μm microag gregate. Raising fertilization, especially raising quantity of organic fertilizer or blending organic fertilizer and in organic one, it is benefited for forming the bigger diameter aggregate.