PURPOSE: To provide a controlling method of printing of a thermal transfer printer which enables stabilization of a print quality and prolongation of a printable time by adding voltage drop correction and low-battery correction to usual printing correction such as history correction, area correction and temperature correction.

CONSTITUTION: Values obtained by counting the number of on-dots of a printing head are ranked in the same way as in usual area correction 3, ranks thus obtained are combined with ranks obtained by usual history correction 1 and thereby voltage drop correction 2 for correcting an electrification time for a voltage drop occurring in each part of an apparatus is conducted. After a low-battery state showing lowering of a power supply of the apparatus is detected, besides, a ranking table is prepared likewise and low-battery correction is executed.