To provide a fuel supply controller for internal combustion engine by which overheating of an internal combustion engine is prevented.

This controller is provided with a rotation speed detecting means to detect the rotation speed of an internal combustion engine, a load detecting means to detect the load of the internal combustion engine, a fuel supplying means to supply a fuel to the internal combustion engine, and a fuel supply controlling means which controls the supply amount of a fuel by the fuel supplying means based on the detected rotation speed and load, stops the fuel supply by the fuel supplying means when the detected rotation speed exceeds a first set value, and starts fuel supply again when the detected rotation speed is less than a second set value lower than the first set value. When the fuel supply controlling means starts fuel supply again by the fuel supplying means, the supply amount of the fuel by the fuel supplying means is determined based on at least either the detected load or the vehicle speed to give lean condition.