Abstract: To investigate the effect of two exogenous signal molecules—ethylene and methyle jasmonate( Me JA) on the wounding physiological reaction of fresh- cut fruit and vegetables,fresh- cut pumpkin was treated with exogenous ethylene and Me JA respectively,then stored at 4 ℃.Value of chromatism,weight loss,malondialdehyde( MDA) content,lipoxygenase( LOX) activity and phenylalnine ammonialyase( PAL) activity were analyzed. The results indicated that ethylene and Me JA could significantly maintain the color and weight of fresh- cut pumpkin when compared with the controlled( p < 0.05).The two treatment methods could inhibit the increase of MDA content during the later stage of storage and the occurrence of membrane lipid peroxidation. The effect of exogenous ethylene and Me JA on LOX were similar,but the effect of ethylene was more obvious( p < 0.05). The defense reaction of fresh- cut pumpkin was started and the damage of mechanical injury on plant tissue was reduced by two signal molecules.