Abstract: Effects of different concentrations of chitosan(CTS)pretreatment on some physiological indexes were investigated in hulless barley seedlings under 12% of the Polyethylene glycol(PEG)by solution culture method. The results show that the contents of water content, relative chlorophyll and soluble protein all decreased under 12% PEG stress; but opportune concentration CTS pretreatment is able to inhibit the decrease of water content, and also helps improve the content of relative chlorophyll and the content of soluble protein to some extent. In conclusion, appropriate concentration CTS pretreatment can enhance drought resistance of hulless barley seedlings and alleviate the damage caused by water stress.