A fuel injection controller of an internal combustion engine calculates a correction value for correcting a rotation fluctuation amount among cylinders of the engine during idling stabilization control. The controller calculates an average change in correction value over M number of changes in correction value for the cylinder. If it is determined that the average change is less than or equal to athreshold value a, it is determined that the correction value is stabilized. The correction value at that time is fixed as a learning value of a deviation amount of an injection characteristic amongthe cylinders. Thus, the fuel injection controller suitably achieves accurate learning of an inter-cylinder variation in the injection characteristic of the fuel injection valve and performing of thelearning in a short time.