The signal transmission circuit is provided, said signal transmission circuit being capable of stable operations even with a source power of low voltage and a fast operation. The signal transmission circuit comprises plural stages of circuit in each of which the pulse voltage according to the driving pulse is sequentially outputted. The circuit of each stage includes: the output transistor T12 for outputting the pulse voltage to the source, according to the driving pulse; the bootstrap capacitor C1 connected between the gate and the source of the output transistor; the first charging transistor T11 for charging the bootstrap capacitor; the first and the second discharging transistor T13 and T14 for discharging the electric charge of the bootstrap capacitor; and the logical circuit which (i) turns on the first and the second discharging transistor, according to the driving pulse for each circuit of the other stages, and (ii) turns off the first and the second discharging transistor, according to the gate signal of the charging transistor.