An apparatus for controlling ignition timing during a shift in a vehicular automatic transmission is provided that is capable of suppressing shift shock in the event that input torque of the automatic transmission is affected by external changes, such as changes in fuel and air pressure and the like, by adjusting immediately to those changes. This control apparatus is provided with an ignition timing controller that controls an ignition timing retard amount; a calculator that calculates a basic retard amount; a detector that detects an engine retard amount; a determinator that determines a retard correction value based on a shift mode of the automatic transmission and the like; and a corrector that corrects the ignition timing retard amount of the controller based on the retard correction value, the basic retard amount, and the engine retard amount.