The secondary salinization of grassland soil is the mam reason for the formation of secondary saline-alkaline soil pathes in grasslands in Songnen Plain.Inthe presence of potential salinization factors such as dry climate and high underground water level the secondary salinization of grassland soil was induced because vegetation had been ruined due to strong anthropogenic interference.Therefore,the secondary saline-alkaline soil in grassland had its special profile and physical and chemical characterstics.It is suggested that to protect and recover vegetation is an effective way to prevent and improve secondary saline-alkaline grassland soil in Songnen Plain.