Abstract: Soil exchangeable Ca and Mg contents were determined in continuous maize cropping system under different fertilization and plastic film mulching in the long-term brown earth experimental station (started in 1987) in Shenyang Agricultural University, Laoning Province, China. The results show that the contents of soil exchangeable Ca (0-40 cm) are from 1.34 g/kg to 2.52 g/kg, soil exchangeable Mg from 0.30 g/kg to 0.66 g/kg. Soils in this area are very rich in Ca and Mg, the deficiency of Ca and Mg in maize is rarely happened. Besed on the 24 years experiment, the exchangeable soil Ca and Mg in the topsoil (0-20 cm) keep increasing in plots applied with manure, decreasing in plots applied with inorganic fertilizers. The exchangeable Ca and exchangeable Mg contents in topsoil applied with inorganic fertilizers are lower than in subsoil (20-40 cm). The exchangeable Ca and Mg in topsoil are enhanced in the treatments of plastic film mulching and chemicalfertilizer addition. There are significant positive correlations between exchangeable Ca and Mg with pH in these treatments, which means the exchangeable Ca and Mg contents are influenced by soil pH.