Perennial ryegrass（Lolium perenne L.） seedlings were treated with various of concentrations of NaCl（A）,NaHCO₃（B）, NaCl and NaHCO₃（C） to investigate the distribution of three protective enzymes in Lolium perenne L.When the concentration of two kinds of single salt（NaCl, NaHCO₃） were 100, 200, 300, 400 mmol/L（A1, A2, A3,A4） and 30, 60, 90, 120 mmol/L（B1, B2, B3, B4）, and the concentrations of one mixed salt（NaCl + NaHCO₃） were100, 200, 300, 400 mmol/L（C1, C2, C3, C4）, respectively. After stressed, polyacrylamide gel electrophoresis was used to separate SOD, POD and CAT from ryegrass plants and establish electrophoresis pattern. The results showed that 3 enzymes were expressed in ryegrass plants, with variations in zymogram distribution and enzyme activity under different saline-alkali stress conditions, allowing the plants to adapt to the unique biochemical reactions occurring within cells under salt stress.