Abstract: To provide a theoretical reference for carrying soil of bio-slope engineering,the organic material's and absorbent agent ’s effects on carrying soil ’s moisture constants and permeability coefficient should be studied.Sandy soil,organic material and absorbent agent were selected to carrying on proportional experiments.The research result shows that carrying soil ’s moisture constants increase with the increment of organic material content,and its permeability coefficient markedly increase with organic material content exceeding 20%.Increment of absorbent agent contributes to increase carrying soil's saturated water capacity,field water capacity and effective water capacity.Furthermore，it can decrease carrying soil ’s wilted water capacity.That is of great advantage to reserve much effective water for plants ’growing and their survival in dry seasons.