The control apparatus for an internal combustion engine of the present invention comprises: a fuel supply device for supplying fuel to the internal combustion engine; a fuel tank for retaining fuel; a purge device for purging fuel vapor, produced in the fuel tank, into an intake system of the internal combustion engine; a purge correction amount updating device for calculating a purge correction amount for correcting an amount of fuel to be supplied by the fuel supply device, depending on the amount of fuel vapor purged by the purge device; a target air-fuel ratio setting device for setting a target air-fuel ratio depending on a running state of the internal combustion engine; and an update amount setting device for updating the purge correction amount depending on the target air-fuel ratio set by the target air-fuel ratio setting device.