Abstract: An up-counter counts pulses of a first pulse train of a variable frequency during each pulse-duration of pulses generated corresponding to the angular position of a crankshaft of an engine. The so counted value is transferred to a down-counter which counts pulses of a second pulse train with a constant frequency so as to diminish its transferred content. The down-counter produces an output signal as an ignition timing signal when its content decreases down to a predetermined value. In the ignition timing control device of such type, the first pulse train of the variable frequency can be provided by a novel advance angle establishing means in which a given short time period is divided into two time portions and from which two pulse trains of different frequency from each other are outputted for the respective time portions, the ratio of sharing being controlled in accordance with the number of revolutions of the engine and the opening value of the throttle.