Abstract: To investigate the effect of lipoxygenase(LOX) on the intramuscular lipid oxidation in pork due to high pressure treatment,porcine longissimus muscle which had been removed of LOX was used as material,after addition of some LOX extracted from fresh porcine longissimus muscle or exogenous LOX(from soybean),the samples were treated at 600MPa-50℃ or 350MPa-20℃ before 6 days storage at 4℃,then the activities of LOX and TBARS values in all samples after high pressure treatment and after cold storage were analyzed. The results showed that LOX had important role on the start-up of intramuscular lipid oxidation due to high pressure treatment,but it had no effect on the last oxidation state(TBARS value) of chilled samples. During cold storage after high pressure treatment,the lipid oxidation was mainly the auto-oxidation,and the role of LOX was very limited,even 5 times of exogenous LOX was added,the TBARS value of the chilled samples only increased a little. So the role of LOX on the intramuscular lipid oxidation in pork due to high pressure treatment was very limited compared to auto-oxidation.