In order to understand the effects of maize straw，clover straw and vermicompost on the physical-chemical properties of silty loam soil，and to accurately evaluate the role of organic material application in the soil improvement of the Yellow River floodplain in Jiangsu province，under 28℃ and 80% soil field water holding capacity，eight treatments(CK，M，C，V，MC，MV，CV and MCV，CK means control check，M means maize straw，C means clover straw，V means vermicompost)were used to test the changes of physical-chemical properties in silty loam soil after 180 d culture. The results showed that the pH and conductivity of the silty loam soil decreased and increased separately with the addition of three kinds of organic materials，and the order of effect was clover straw>maize straw>vermicompost.The pH of M，C，V decreased by 4.12%，8.05% and 1.62%，respectively，and the conductivity increased by 77.55%，288.06% and 56.34%，respectively. The addition of three kinds of organic materials increased the proportion of soil macroaggregate and the mean weight diameter of soil aggregate(MWD)，and the order of effect was maize straw>clover straw>vermicompost. Among them，MWD of M，C，V increased by 154.20%，71.92% and 12.99%，respectively. All three kinds of organic materials increased the content of soil organic carbon，total nitrogen，alkali hydrolyzed nitrogen，available phosphorus and available potassium.The effects of maize straw and clover straw on the content of soil organic carbon，total nitrogen and available potassium were significantly stronger than that of vermicompost，and the effect of vermicompost on the content of soil available phosphorus was stronger than that of maize straw and clover straw.In a word，the application of three kinds of organic materials can improve the physical-chemical properties of silty loam soil.Considering the balanced supply of nutrients and the improvement of aggregate structure，the effect of combination application of three organic materials is better.