an ignition time controlling device having a trigger circuit employing a programmable unijunction transistor which will be on at a timing when a primary short - circuiting current of an ignition coil is at or a little past a peak . the device includes a charging and discharging circuit for the primary short - circuiting current ; a switching controlling circuit interrupting the primary short - circuiting current when the trigger circuit is on ; an ignition coil inducing a high voltage in a secondary coil when the primary short - circuiting current is interrupted ; a spark plug generating a spark on receiving the high voltage of the secondary winding and an angle advancing circuit connected between the programmable unijunction transistor and the switching controlling circuit . the angle advancing circuit breaks over at a set value of the primary short - circuiting current or the voltage on the primary winding of the ignition coil and operates the switching controlling circuit prior to the operation of the programmable unijunction transistor .