Desertification is one of the most severe environmental and social problems. Chemical prevention technology is an important method of desertification control, which is of low-cost, effective and simple for application. In this paper, a kind of networking biodegradable aqueous polyurethane sandy-soil stabilizer was synthesized by polyether glycol, toluene diisocyanate (TDI), dimethylolpropionic acid (DMPA), trimethylolpropane (TMP), soluble starch, and some other materials. The effects of the content of soluble starch on the property of the sandy-soil stabilizer were studied. The results showed that, while the content of soluble starch increased, the viscosity and the average particle size of the emulsion increased, the ability of water conservation and the biodegradation enhanced. From this experiment, aqueous polyurethane sandy-soil stabilizer was prepared, which not only good for sandy-soil stabilization and water retention, but also good for biodegradation after a long run, which was do well in environmental protection.