Abstract: Taking‘Tunis’soft-seeded pomegranate seedlings as the test material,three irrigation（W1,the upper and lower limits of irrigation were 35%-45%of the field water holding capacity;W2,the upper and lower limits of irrigation were 55%-65%of the field water holding capacity;W3,the upper and lower limits of irrigation were 75%-85%of the field water holding capacity）and four N application(N0,0g·kg^-1;N1,0.1g·kg^-1;N2,0.2g·kg^-1;N3,0.3g·kg^-1)treatments were set up.The effects of different treatments on the relative water content（RWC）,photosynthetic pigment content（chlorophyll and carotenoids）,membrane permeability indexes(relative electrical conductivity（REC）and malondialdehyde （MDA）content,hydrogen peroxide （H₂O₂）content,superoxide anion（■）production rate and antioxidant enzyme activity were investigated in pots,and heat map clustering and principal component analysis were performed for each index after 40days of treatment,in order to provide reference for cultivating of soft-seeded pomegranate.The results showed that the irrigation level of 35%-45%（W1）of field capacity significantly inhibited the activities of SOD,APX,POD and CAT,and decreased the total chlorophyll and carotenoid content.However,suitable nitrogen application could alleviate the inhibition effect,and high nitrogen application could aggravate the drought stress degree of pomegranate.The activities of SOD,APX,POD,CAT and photosynthetic pigment contents were relatively high,but the contents of REC,MDA,■and H₂O₂ were relatively low when the irrigation amount was 55%-65%of field capacity （W2）.When the irrigation amount was 75%-85%of field capacity（W3）,the indexes were slightly decreased compared with that of W2,and the pomegranate treated with N2 and N3 had higher photosynthetic pigment content and antioxidant enzyme activity under both W2and W3conditions.In conclusion,the clustering and principal component analysis showed that W2N2 was the best water and nitrogen operation mode under this experimental condition.