To provide such a base multiplying agent capable of being used for crosslinking reaction, for example of a epoxy compound and the like, that generates another base by action of a base, and can efficiently perform base multiplying reaction, and a base-reactive curable composition using the base multiplying agent.The base generating agent of the invention is represented by the following formula (1): (In the formula (1), X represents a hydrogen atom, a substituted alkyl group or an unsubstituted alkyl group; Y represents a substituted or unsubstituted alkylene chain; and n represents an integer of from 1 to 4.)