An electromagnetic relay in which terminal pieces carrying fixed contact pieces can be assembled in the case for the electromagnetic relay from above. The case consists of a main case accommodating an electromagnet unit, a terminal case accommodating a contact unit and mounted on the main case, and a cover which is mounted on the terminal case. Each of the terminal pieces is fitted into a mounting position in a certain direction to be made immobile in any other direction perpendicular thereto. The cover is provided with a plurality of projections each of which engages with one of the terminal pieces to prevent it from moving in the said certain direction. Thus, the terminal pieces may be assembled from the upper end of the terminal case, and the work required for this assembly process may be significantly reduced. According to this structure, since the terminal case may be integrally provided with a bottom wall which separates the contact unit in the terminal case from the electromagnet unit accommodated in the main case, a better insulation can be achieved without in any way complicating the assembly process.