Per every one printing scan of a head, a printing data to be printed by the corresponding scan is divided into L in a scanning direction (lateral direction) and N in a paper feeding direction (longitudinal direction. Concerning each counting blocks identified by l and number of driving rln is counted. Then, with respect to each l, rln are sequentially summed from n=1 to obtain Sl. At every time of summing for deriving Sl, judgment is made whether Sl is greater than a predetermined value R determined in association with a power source capacity. When judgment is made that Sl is greater than R, printing of a printing data corresponding to the counting blocks of 1 to (n−1) with respect to n−1 which is one smaller value that the value n of the counting block upon judgment that Sl is greater than R, is performed, and then paper feeding is performed for the corresponding counting blocks. Thus, lowering of throughput can be restricted with optimally using the power source capacity of the apparatus.