Abstract: A fuel control apparatus for an internal combustion engine comprises, an air intake quantity detector to detect a parameter related to an air intake quantity for the engine, a filter for filtering an output from the air intake quantity detector, a switch for changing the filter coefficient of the filter on the basis of operational conditions of the engine, a controller to control a fuel supply quantity to the engine on the basis of the output of the filter, and a corrector to correct the fuel supply quantity depending on an error between an output from the filter and another output from the same at a predetermined crank angle when the error exceeds a predetermined value, wherein the predetermined value is changed depending on the filter coefficient which is changed by the switch.