Two Rhododendron cultivars which had poor drought resistance:Rh.'Lan Yin'and Rh.'Ningbo Hong'were selected as test materials.Based on the observation of the external morphology and the determination of physiological indexes,effects of exogenous ealicylic acid on drought-resistance of Rhododendron were evaluated.The results showed that after applying different concentrations of salicylic acid,degree of drought damage decreased in Rh.'Ningbo Hong'with the concentrations of 0.3,0.5 mmol · L-1 and Rh.'Lan Yin'with 0.3,0.5 and 0.7 mmol · L-1.The suitable concentrations of salicylic acid could improve free water content,leaf bound water content and total water content of Rhododendron,keep lower free water/bound water,promote the syntheses of chlorophyl1,increase soluble sugar,soluble protein and proline in cells such as cell infiltration through concentration regulating substances,prevent the membrane damage and the accumulation of MDA and H2 O2,and protect the activity of SOD and POD.Therefore,it can reduce damage caused by drought stress and improve the drought resistance of Rhododendron.