Abstract: After treated with CaCl2, the flesh discs of “Golden Dilicious” apple was significantly increased in Ca2+ content and decreased in K+ leakage, Ca2+ at different concentrations could enhance activities of superoxide dismutase and catalase, increase contents of glutathione and ascorbic acid, but decrease H2O2 content and relative electroconductance rate at different levels. It is suggested that the increase in protective enzyme activity and protective substance content of fruit by Ca2+ would favour to protect cell membrane structure.