Sewage sludge may be exploited as water retaining agent owing to its characteristics of low water permeability and drying rate,which were considered as the technical barrier of sewage sludge application. Plot and pot culture of corn were conducted in the experiment to study the influences of different content and placement of sewage sludge on water retention.Water content,water loss and water loss rate in plot culture together with soil water content and plant biomass in pot culture were measured and analyzed systematically. The treatment with high sewage sludge amount had a significant effect of water retaining;sewage sludge had a better effect in pot culture and a worse effect in plot culture than the treatment of SAP(super absorbent polymer).Different placement of sewage sludge experiment showed that placing sewage sludge in a sandwich way was better than just mixing with soil.Especially,placing the sludge in two layers was superior.In summary, sewage sludge has a strong ability of water retention,which requires further investigation.