An apparatus for measuring fuel injection timing has a pulse generator for generating a pulse train composed of pulses one of which is produced each time the engine rotates by a predetermined angle and a counter to which the pulses are applied as count pulses. The counter is controlled so as to be operative only for the period from the time of fuel injection to the time that the associated crank reaches top dead center. As a result, data indicative of the fuel injection advance can be obtained from the counter.