A solid xylylenediamine solidified in a container is extremely excellent in storage stability as compared with a liquid xylylenediamine, and is less degraded by discoloration even when stored in an atmosphere containing oxygen. By charging a liquid xylylenediamine into a container, solidifying the liquid xylylenediamine into a solid xylylenediamine in the container under cooling without delay after the charging, and storing the solid xylylenediamine in the container while maintaining the xylylenediamine in a solid state, the xylylenediamine is stored for a long period of time without causing deterioration of quality such as discoloration.