An electronic firing device of a missile, enabling precise setting of a time delay from several milliseconds up to an hour or more, comprises an energy accumulator formed by a capacitor associated with an energy receiving coil charging the capacitor from an external signal. This signal has a low frequency energy-supply component and a high frequency signal having a series of pulse trains defining a decimal number up to, for example, 10.sup.7. The high frequency signal passes via a coded selective filter supplying, to a memory, a coded value defining a time delay. An oscillator triggered by a security switch supplies clock signals which are divided to provide 1 millisecond pulses counted in a coding circuit in the same code as the memory. This coding circuit and the memory are connected to a comparator which supplies a firing signal when the count reaches the memorized value.