An image recording apparatus according to this invention analyzes image data to be printed, and generates sequence information for defining the moving range of each scanning motion of a recording head and the conveyance amount of a recording medium. The apparatus divides a recording area defined by the generated sequence information into areas so that the processing amounts of a plurality of processing units capable of parallelly executing processes are equal to each other, distributes data of the divided areas to the processing units, and causes each of the processing units to generate recording image data. The apparatus performs recording by controlling driving and a scanning motion of the recording head and conveyance of the recording medium based on the recording image data obtained by the processing units.