PURPOSE: To provide the salt damage-preventing cement additive and the salt damage-preventing cement composition which are mainly used in construction/ building fields.

CONSTITUTION: The salt damage-preventing cement additive comprises a basic chloride compound, and the salt damage-preventing cement composition comprises a cement and the salt damage-preventing additive. The obtained salt damage-preventing cement additive is excellent in chloride ion-catching ability, and when the additive is added to concrete singly or as the composition, the additive exhibits effects such as the chloride ion immersion-preventing effect and remarkable salt damage-preventing effect.