The present invention relates to a novel binder having high bondability and fluidity. The binder of the present invention has a BET specific surface area of 80 to 400 m2/g and is composed of carbonate-containing magnesium hydroxide particles represented by the following Formula (1): MgOH2-xCO30.5x⋅mH2O wherein, x and m satisfy the following requirements: 0.02≤x≤0.7, and 0≤m≤1. Even if the binder of the present invention is prescribed together with a disintegrant or a water-soluble excipient, the binder can improve the tablet hardness without elongating the disintegration time of the tablet and can be applied to direct compression.
