The corn seedlings were treated by different concentrations of salicylic acid in the experiment to study how its growth and development affected.The results showed that fresh weight,seedlings height,chlorophyll content,activities of SOD and POD,MDA and electrolyte leakage rate were significantly affected by the treatment.The growth and development of seedlings were promoted after 1.5 mg/L treatment.The fresh weight and seedlings height were increased by 45.6% and 28.2% respectively.Also,Chlorophyll content,activities of SOD and POD were increased by 147.7%,53.8% and 25.3% respectively.The MDA and electrolyte leakage rate were decreased by 9.6% and 17.3% respectively.