In a fuel injection timing control apparatus having a sensor for generating a signal indicating the actual timing of fuel injection in response to the fuel pressure occurring at the time of fuel injection for controlling the fuel injection timing in the mode of closed-loop control using the signal as a feedback signal, when the sensor stops producing the signal, the control mode is changed to the mode of open-loop control so as to continue the control operation of the fuel injection timing, and the state of zero injection of the fuel injection pump is distinguished from the occurrence of a malfunction in the sensor.