To provide a technology that reduces the size of a lighting surge protection circuit.

The lighting surge protection circuit 10 has a surge protection function for signals in two systems, a first line L1 and a second line L2, and includes first to third surge absorbers LG1 to LG3, and a RG circuit 20 disposed on the inner side than the first to third surge absorbers LG1 to LG3. The RC circuit 20 includes: a first resistor R1 directly provided in a first line L1; a second resistor R2 provided in a second line L2; and a capacitor C provided on the inner side than the first and second resistors R1, R2 and interposed between the first and second lines L1, L2.