The effect of turnover of farm-manure,green-manure,wheat straw and mixed application of 1/2 green-manure and 1/2 wheat straw into soil on soil fertility in the rotation of winter wheat and corn in Shangdong Province was studied.Experiment showed that these manuring measures not only increased total amount of organic matter,but also improved its quality,and the stability of aggregates and nutrient condition in the soil.For the aggregates in diameter from 0.25mm to 3.0 mm,the total content of organic matter increased with the increase in size of aggregates.The proportion of Gl fraction of the complexes tended to increase,while the proportion of G₂ fraction tended to decrease with the increase in size of aggregates.The G₁/G₂ ratio was getting increased with the increase in size of aggregates.