Effects of tillage modes and straw return on soil organic carbon（SOC）and rice yield were studied in direct seeding rice field.Results showed that straw return significantly increased SOC contents,and soil tillage modes had significant effects on the vertical distribtion of SOC.There was a significant positive correlation between SOC content and rice yield（R2=0.712 9**,n=6）,and significant positive correlation between SOC and TSN（R2=0.860 9**,n=43）.These evidenced that straw return promoted SOC content,stabilized crop productivity in direct rice field,and achieved the win-win effect of grain safety and environmental safety.