To provide a closed electromagnetic relay preventing a malfunction of the electromagnetic relay body caused by a sealant filled, even if the electromagnetic relay body incorporated into an insulating base is inserted into a box-like insulation cover, and the sealant is filled in a fitting space between the insulating base and the insulation cover.

In the electromagnetic relay, its body incorporated into the insulating base is inserted into the box-like insulating cover having an opened surface, the insulating base is fitted into the insulating cover to close the opened surface of the insulating cover with the insulating base, the sealing agent is filled in the fitting space between the insulating base and the insulating cover to seal up the fitting space. A line groove or a finely rugged surface is formed on at least one of an outer surface of the insulating base and an inner surface of the insulating cover which are in opposite contact with each other on fitting parts of the insulating base and the insulating cover to suppress flowing of the sealing agent into the body.