Abstract: By using 0.4 mmol/L SNP to deal with the pear leaves before hand, after 3d stress them with High temperature. The in dividual figures were them taken after 10h. The result shows that using SNP in the density of 0.4 mmol/L to treat the diseased pear leave can raise the activity of GPX、GX 、POD、SOD、CATand reduce the activity of LOX . It can de initially confirmed that SNP in a relatively low density can palliate harm to pear leaves unser Hidh temperature stress