Abstract: Abstract: Watermelon seeds viability often decreased in process of natural storage, so it is significant to enhance the seeds germination rate and germination power of watermelon foe watermelon seed production , storage and utilization . In this study, the aged watermelon seeds were selected as material, soaked by different concentrations of salicylic acid (SA), calcium nitrate and gibberellic acid (GA3), to study the effects on germination rate, related physiological and biochemical indexes of aged watermelon seeds. The results show that the activity of aged watermelon seeds was obviously increased after soaking, and the best treatment to promote germination was Ca(NO3)210mmol/L. Besides, conductivity and soluble sugar content of seeds lixivium, and MDA content of seeds were decreased obviously after treated by SA, Ca(NO3)2 and GA3, and SA treatment had the best obvious effects.