A controller (40) of a vehicle internal combustion engine (10) that is automatically stopped and restarted under a prescribed condition related to operation of the vehicle is disclosed. The engine (10) includes an output shaft (11), a starter (20) constantly meshed with the output shaft (11), and a throttle valve (12) regulating the intake air amount supplied to the engine (10). After the engine (10) has been subjected to an automatic stopping procedure, the controller (40) restarts the engine (10) when a restarting condition is met, and the controller (40) uses the starter (20) to restart the engine (10) if the engine speed is in such a predetermined range that autonomous operation of the engine (10) cannot be restored. The controller (40) temporarily opens the throttle valve (12) on the condition that the engine speed at the time when the restarting condition is met is not zero and is in the predetermined range.