A solid state relay (2, 23) comprising: a pair of input terminals (5a, 5b, 29a, 29b); a light-emitting element (9, 27) between the pair of input terminals (5a, 5b, 29a, 29b); a light-receiving element (10, 28) configured to carry out photoelectric conversion on light outputted from the light-emitting element (9, 27) and configured to output current; a pair of output terminals (6a, 6b, 32a, 32b) configured to connect to an AC power supply (3, 24) and a load (4, 25), the pair of output terminals (6a, 6b, 32a, 32b) including a first output terminal (6a, 32a) and a second output terminal (6b, 32b); a first connection line (11, 33) connecting a first end of the light-receiving element (10, 28) to the first output terminal (6a, 32a); a second connection line (12, 35) connecting a second end of the light-receiving element (10, 28) to the second output terminal (6b, 32b); a switching element (13, 37) between the first connection line (11, 33) and the second connection line (12, 35) and configured to be turned on by the current outputted from the light-receiving element (10, 28); a snubber circuit (14, 38) between the first connection line (11, 33) and the second connection line (12, 35) and including a capacitor (C1, C2) and a resistor (R2, R11), the capacitor (C1, C2) and the resistor (R2, R11) connected in series, wherein the resistor (R2, R11) is connected in series in the first connection line (11, 33) between the first end of the light-receiving element (10, 28) and an end of the switching element (13, 37) via a node (17,45), wherein the node (17, 45) connects an end of the switching element (13, 37) to the first connection line (11, 33), characterized in further comprising an over-current protection element (21, 34) that is connected in series in the first connection line (11, 33) between one end of the resistor (R2, R11) and the node (17, 45) to which the end of the switching element (13, 37) is connected, wherein the over-current protection element (21, 34) is a fuse. a pair of input terminals (5a, 5b, 29a, 29b); a light-emitting element (9, 27) between the pair of input terminals (5a, 5b, 29a, 29b); a light-receiving element (10, 28) configured to carry out photoelectric conversion on light outputted from the light-emitting element (9, 27) and configured to output current; a pair of output terminals (6a, 6b, 32a, 32b) configured to connect to an AC power supply (3, 24) and a load (4, 25), the pair of output terminals (6a, 6b, 32a, 32b) including a first output terminal (6a, 32a) and a second output terminal (6b, 32b); a first connection line (11, 33) connecting a first end of the light-receiving element (10, 28) to the first output terminal (6a, 32a); a second connection line (12, 35) connecting a second end of the light-receiving element (10, 28) to the second output terminal (6b, 32b); a switching element (13, 37) between the first connection line (11, 33) and the second connection line (12, 35) and configured to be turned on by the current outputted from the light-receiving element (10, 28); a snubber circuit (14, 38) between the first connection line (11, 33) and the second connection line (12, 35) and including a capacitor (C1, C2) and a resistor (R2, R11), the capacitor (C1, C2) and the resistor (R2, R11) connected in series, wherein the resistor (R2, R11) is connected in series in the first connection line (11, 33) between the first end of the light-receiving element (10, 28) and an end of the switching element (13, 37) via a node (17,45), wherein the node (17, 45) connects an end of the switching element (13, 37) to the first connection line (11, 33), characterized in further comprising an over-current protection element (21, 34) that is connected in series in the first connection line (11, 33) between one end of the resistor (R2, R11) and the node (17, 45) to which the end of the switching element (13, 37) is connected, wherein the over-current protection element (21, 34) is a fuse.