To accurately control all the time the operation of an engine to a target fuel infection timing by varying feed back control constant according to the stroke of a timing control valve.

A fuel injection timing control device is equipped with a means 22 for setting up a target fuel injection timing according to an engine operation state; a computing means 24 for actual fuel injection timing; and a means 25 which drives a timing control valve 3 on a deviation between the target injection timing and the actual injection timing to feedback-control the fuel injection timing, and moreover equipped with a means 26 for computing the stroke quantity of the timing control valve 3 and a correcting means 27 for varying the constant of the feedback control means 25 according to the above stroke quantity.