PURPOSE: To reduce transmission of shock at the time of switching to an occupant in a vehicle by switching port injection from/to in-cylinder injection only when the lock-up of automatic transmission is not worked.

CONSTITUTION: As fuel is injected by a port injection valve 1p into the intake port of an engine 1, and the fuel is directly injected into the cylinder of the engine 1 by an in-cylinder injection valve 1c. It is judged by an ECU 3 which is formed as a digital computer whether or not a drive condition is changed exceeding the boundary between a predetermined port injection region and an in-cylinder injection region, and the ECU 3 also has a function as a lock-up operation detection means of an automatic transmission 2. Port injection and in-cylinder injection are switched from one another only when the drive condition is changed exceeding the boundary between the port injection region and the in-cylinder region, and only when a lock-up operation signal is not output by the lock-up operation detection means. Torque fluctuation is absorbed by a torque converter and shock to be transmitted to occupants in a vehicle can thus be reduced.