To provide an electronic relay clearly discriminating a circuit failure from no input signal.

A normal input signal N1 and a reverse input signal R1 having a reverse relation to the normal input signal N1 are supplied to a signal processing part 1, and a normal control signal N2 corresponding to the normal input signal N1 and a reverse control signal R2 corresponding to the reverse input signal R1 are output from the signal processing part 1. When the signal processing part 1 supplies the normal control signal N2, a normal relay part 2 outputs a normal output signal N3 as an existence signal. When the reverse control signal R2 is supplied from the signal processing part 1, the reverse relay part 3 outputs the reverse output signal R3 as an existence signal. Except in change of the normal input signal N1 or the reverse input signal R1 from a non-signal to an existence signal, the signal processing part 1 controls the normal relay part 2 and the reverse relay part 3 to keep the present conditions of the normal output signal N3 and the reverse output signal R3.